Internal opposition to Turkish neutrality came from ultra-nationalist circles and factions of the military that wished to incorporate the Turkic populated areas in the Soviet Union by allying with Germany. This almost erupted into a coup d'etat against the government. Leading pan-Turkists including Alparslan Türkeş, Nihal Atsız, and Şaik Gökyay were arrested and sentenced time in prison in the Racism-Turanism trials.British Prime Minister Winston Churchill traveled to Ankara on January 1943 for a conference with President İnönu, to urge Turkey's entry into the war on the allied side. Churchill met secretly with İnönü inside a railroad car at the Yenice Station near Adana. By 4–6 December 1943, İnönü felt confident enough about the outcome of the war, that he met openly with Franklin D. Roosevelt and Winston Churchill at the Second Cairo Conference. Until 1941, both Roosevelt and Churchill had thought that Turkey's continuing neutrality would serve the interests of the Allies by blocking the Axis from reaching the strategic oil reserves of the Middle East. But the early victories of the Axis up to the end of 1942 caused Roosevelt and Churchill to re-evaluate a possible Turkish participation in the war on the side of the Allies. Turkey had maintained a decently-sized Army and Air Force throughout the war, and Churchill wanted the Turks to open a new front in the Balkans. Roosevelt, on the other hand, still believed that a Turkish attack would be too risky, and an eventual Turkish failure would have disastrous effects for the Allies.İnönü knew very well the hardships which his country had suffered during decades of incessant war between 1908 and 1922 and was determined to keep Turkey out of another war as long as he could. The young Turkish Republic was still re-building, recovering from the losses due to earlier wars, and lacked any modern weapons and the infrastructure to enter a war to be fought along and possibly within its borders. İnönü based his neutrality policy during the Second World War on the premise that Western Allies and the Soviet Union would sooner or later have a falling out after the war. Thus, İnönu wanted assurances on financial and military aid for Turkey, as well as a guarantee that the United States and the United Kingdom would stand beside Turkey in the event of a Soviet invasion of the Turkish Straits after the war. In August 1944 İnönü broke off diplomatic relations with Germany and on 5 January 1945, İnönü severed diplomatic relations with Japan. Shortly afterwards, İnönü allowed Allied shipping to use the Turkish straits to send supplies to the Soviet Union and on 25 February 1945 he declared war on Germany and Japan. For this Turkey became a founding member of the United Nations.