Nyon Conference The Nyon Conference was a diplomatic conference held in Nyon , Switzerland in September 1937 to address attacks on international shipping in the Mediterranean Sea during the Spanish Civil War . The conference was convened in part because Italy had been carrying out unrestricted submarine warfare , although the final conference agreement did not accuse Italy directly ; instead , the attacks were referred to as " piracy " by an unidentified body . Italy was not officially at war , nor did any submarine identify itself . The conference was designed to strengthen non - intervention in the Spanish Civil War . The United Kingdom and France led the conference , which was also attended by Bulgaria , Egypt , Greece , Romania , Turkey , the Soviet Union and Yugoslavia . The first agreement , signed on 14 September 1937 , included plans to counterattack aggressive submarines . Naval patrols were established ; the United Kingdom and France were to patrol most of the western Mediterranean and parts of the east , and the other signatories were to patrol their own waters . Italy was to be allowed to join the agreement and patrol the Tyrrhenian Sea if it wished . A second agreement followed three days later , applying similar provisions to surface ships . Italy and Germany did not attend , although the former took up naval patrols in November . In marked contrast to the actions of the Non - Intervention Committee and the League of Nations , this conference succeeded in preventing attacks by submarines . Context and organisation . The Non - Intervention Committee , a group of twenty - four nations set up in 1936 and based in London , had attempted to restrict the flow of weapons to the parties of the Spanish Civil War . For the United Kingdom , it formed part of the policy of appeasement towards Germany and Italy and aimed at preventing a proxy war – with Italy and Germany supporting Franco ' s Nationalist Coalition on one side and the Soviet Union supporting the Republican faction on the other – from escalating into a major pan - European conflict . An Anglo - Italian " Gentleman ' s Agreement " had been signed on 2 January 1937 , with each party respecting the rights of the other in the Mediterranean and aimed at improving Anglo - Italian relations . In May 1937 , Neville Chamberlain succeeded Stanley Baldwin as British Prime Minister , and adopted a new policy of dealing directly with Germany and Italy . The British believed they could convince Italy to abandon Germany through appeasement . Under a Non - Intervention Committee plan , neutral observers were posted to Spanish ports and borders . The plan also assigned zones of patrol to the United Kingdom , France , Germany and Italy , and patrols began in April . Following attacks on the German cruiser " Leipzig " on 15 and 18 June , Germany and Italy withdrew from the patrols . The United Kingdom and France offered to replace Germany and Italy in patrols of their sections , but the latter powers believed these patrols would be too partial . The British Admiralty proposed four plans in response to attacks on British shipping , favouring sending significant naval resources to the Mediterranean as the best solution ; previous control measures had been widely evaded . As suspected by the other powers , Italy was behind some of these attacks . Whilst officially being at peace , the Italian leadership had ordered the commencement of unrestricted submarine warfare , referred to in discussion as a campaign of piracy without mention of Italy . These plans would be the basis for a Mediterranean meeting , suggested by French Foreign Minister Yvon Delbos . Meanwhile , on the night of 31 August to 1 September , the Italian submarine " Iride " unsuccessfully attacked the British destroyer " Havock " with torpedoes , between the Gulf of Valencia and the Balearic Islands , strengthening British Foreign Secretary Anthony Eden ' s sceptical stance towards Italy . The attack led the British representative in Rome to protest to the Italian Minister of Foreign Affairs , but without response . Up to 60 , 000 Italian volunteers were now operating in Spain , and the removal of foreign nationals was discussed by the Non - Intervention Committee . Italy had made a declaration that it would stop Italian volunteers from fighting in Spain on 7 January 1937 , and put a moratorium on volunteers on 20 January , also agreeing to support limitations on the number of volunteers on the 25th . Italy continued to request that belligerent rights be given to the Nationalists and Republicans , so both would gain the right to search vessels for contraband , thus removing the need for naval patrols . This request was opposed by the United Kingdom , France and the Soviet Union . British recognition of Italian sovereignty over Abyssinia following the Second Italo - Abyssinian War was an important issue during Anglo - Italian discussions in August 1937 . Following Eden ' s disagreement with Chamberlain and Lord Halifax , Leader of the House of Lords and influential politician , over the issue , any agreement recognising Italian sovereignty was postponed until after the planned shipping conference had taken place . On 5 or 6 September , the British arranged a conference for all parties with a Mediterranean coastline , along with Germany . The conference was to be held at Nyon , Switzerland – Geneva was avoided because Italians associated it with the actions of the League of Nations over the Abyssinian Crisis . The United Kingdom agreed to France ' s request to extend an invitation to the Soviet Union , but blocked France ' s attempt to invite a representative from Republican Spain . Portugal expressed surprise at not being invited . Camille Chautemps , the new French Prime Minister , opposed direct intervention on the Spanish question . The Soviet Union accepted the invitation , indicating that it would use the opportunity to blame Italy for the attacks on shipping . The Soviet government formally accused the Italians of sinking two Soviet merchant vessels , the " Tuniyaev " and the " Blageav " , an accusation the Italians described as " aggressive and offensive " . This was perhaps an attempt by the Soviet Union to push Italy and Germany away from the conference . Germany rejected the invitation , stating that piracy and other issues the conference was to discuss should be handled only by normal meetings of the Non - Intervention Committee , not a conference like Nyon . The United Kingdom and France rejected this suggestion , and continued to prepare for the conference . Soon after , the Italians similarly declined . The Non - Intervention Committee , it said , also had the advantage of including other European powers , notably Poland and Portugal . Provisions . British and French naval staffs rejected the idea of a convoy system in draft proposals . The British wanted to curb submarine activity , on the theory that focusing on covert submarine attacks would help avoid confrontation , whereas the French considered surface vessels and aircraft just as important . The French protested at a plan to create multi - nation squadrons , unhappy at the prospect of French ships coming under foreign command . On 8 September , plans were discussed in the British Cabinet , including the setting up of eight groups of three destroyer s for the western Mediterranean . Preliminary talks with the French were held on 9 September , and the conference began on the 10th . Proceedings took two forms : discussions between the British and French , and formal meetings of all attending parties . Many of the other nations opposed the participation of the Soviet Navy in the Mediterranean , so the United Kingdom and France agreed to handle Aegean patrols . This was , perhaps surprisingly , accepted by the Soviet Union . The conference ended on 14 September with the signing of the " Mediterranean Agreement " . Signatories were the countries of Bulgaria , Egypt , France , Greece , Romania , Turkey , the United Kingdom , the USSR and Yugoslavia . The agreement noted attacks on neutral shipping by submarines , in contravention of the London Naval Treaty ( signed in 1930 ) and the Submarine Protocol , part of the Second London Naval Treaty ( signed in 1936 ) . The agreement provided that any submarine that attacked neutral shipping was to be sunk if possible , including submarines in the vicinity of a recent attack that were determined to be responsible for the attack . French and British fleets would patrol the seas west of Malta and attack any suspicious submarines , with the division of patrols between the United Kingdom and France to be decided by their governments . Both countries would patrol the high seas and territorial waters of signatory countries in the Mediterranean . The British would provide slightly more than half the 60 destroyer s needed , with the French providing the remainder and most of the accompanying aircraft . It was agreed that Italy could participate in patrols of the Tyrrhenian Sea if it wished to do so . In the Eastern Mediterranean , British and French ships would patrol up to the Dardanelles , but not in the Adriatic Sea . In this area , signatory countries would patrol their own territorial waters , and would provide any reasonable assistance to the French and British patrols . The future revision of these provisions , including the way the area had been divided into zones , was specifically allowed . Submarine activity would be banned , subject to two exemptions : travel on the surface accompanied by a surface ship , and activity in certain areas for training purposes . Governments would only allow foreign submarines into each of their territorial waters in extreme situations , such as immediate distress . Merchant shipping would also be advised to stick to particular shipping route s . The agreement repeated the suggestion that Italy join in the proposal . Delbos announced that similar proposals about surface craft would be prepared . The provisions of the agreement would come into force on 20 September . The British and French knew that the secret Italian submarine operations had already been paused , but actions to enforce the conference agreement started at midnight on 19 / 20 September . The delegates to the agreement were happy ; " The Times " likened them to cricketers , " reviewing their innings , over by over " . The French and British naval staffs moved to Geneva , where a second agreement was signed on 17 September 1937 . It extended the rules governing submarine warfare to surface vessels , and had the same signatories . Official versions of both agreements were published in French and English . Several proposals were not implemented : for instance , the British Admiral Ernle Chatfield wanted the Spanish parties to be able to verify that the flag a ship was displaying was correct , thereby preventing attacks on British shipping if Republican ships continued to use the British flag as a means of escape . This would have benefited the Nationalists , and the French insisted that this provision be dropped . Greece and Turkey wanted ships with a clear identifying mark to be excluded , so as to avoid being forced to fire on a German or Italian warship . This was rejected , but an amendment was made allowing nations to issue their preferred orders in their own territorial waters . A suggestion to fire at any attacking aircraft was easily passed . Another suggestion on surface ships ( which incorrectly stated no attack had yet been proven ) was eventually toughened with the addition of a clause stating aggressors would be attacked , at the request of the French . A Soviet proposal strengthening the effect of the agreement was made . Aftermath . Meanwhile , on 13 September , Italy was invited to join in the agreement . Italy unequivocally rejected it , refusing to patrol the Tyrrhenian Sea . It demanded " absolute parity " with the United Kingdom and France , meaning the same right of patrol in the Mediterranean . Italy subsequently indicated that its refusal would be reversed if such parity was granted . Meanwhile , on the 15th , Benito Mussolini ' s government sent two submarines to Francisco Franco ' s National Faction . The Soviet Union refused to use routes patrolled by the Italians ; the Turks , Greeks and Yugoslavs refused to let the Italians use their ports . A compromise was signed on 30 September , and Italian patrols started on 10 November . The British government , and in particular Neville Chamberlain , desired better relations with Italy and these were achieved with the signing of the Anglo - Italian Agreements of 1938 . The patrols were a strain on the Royal Navy and the provisions were relaxed with French agreement , effective from January . Submarine activity soon returned and full patrols were resumed in early February . On the whole , submarine activity during this period did not amount to much ; patrols were again relaxed in May , and the agreement suspended in August . The success of the conference was in marked contrast to the failure of the Non - Intervention Committee . The Nationalists and Italians switched to using air power against shipping ; at least one ship was sunk off the Spanish coast by aircraft in the final months of 1937 . In the United Kingdom , Eden described the submarine attacks as savage . He also noted that attacks on submarines would be restricted to suitably extreme circumstances and that the two parties in the war would still not be able to engage neutral vessels . He was keen to avoid an " Anglo - Franco - Soviet bloc " . The British press was in favour of the agreement , although " The Times " and " The Guardian " expressed some concerns . British historians have tended to see the Nyon Conference as an important stand against aggression , with some reservations . Christopher Seton - Watson describes it as a " diplomatic victory " , but Jill Edwards points out that it failed to achieve a change in Italian policy . The agreement created further divisions between Eden as foreign minister and Neville Chamberlain as prime minister . Maxim Litvinov , the Soviet representative , was pleased with the outcome . The agreement also allowed for greater military resources to be deployed to the Mediterranean as needed . Litvinov , in particular , stressed the Soviet Union ' s " indisputable right " to commit naval forces to the Mediterranean ( something Germany and Italy had opposed in meetings of the Non - Intervention Committee ) . He also said he regretted that Spanish merchant shipping had been left out – the other nations believed this would have amounted to formal intervention into the civil war . Aretas Akers - Bouglas , Viscount Chilston and British Ambassador to the Soviet Union , reported that the Soviets considered the conference with " tempered satisfaction " , and that they claimed credit for their delegation ' s role . Elsewhere , French public opinion was strongly in favour of the outcome of the conference , the only criticism coming from the far left that Republican ships would not receive direct protection . The German mood was restrained , where the press were satisfied by the Soviet exclusion from patrols . In Spain , the Republicans – on the verge of disaster – were largely in favour , and the Nationalists strongly against . The Republicans praised the improved safety of the shipping routes , but were somewhat unhappy that belligerent rights had not been granted to both sides . The Nationalists made several complaints , including one over the route recommended to shipping , but none of these resulted in changes to the agreement . The agreement was welcomed by other members of the League of Nations . Italian historians tend to downplay the importance of the Nyon Conference , often seeing it as a mere extension of the Non - Intervention Committee .