The European Union (EU) views enlargement as an historic opportunity to promote stability and prosperity throughout Europe. The criteria for EU membership require candidates to adopt political values and norms shared by the Union by achieving "stability of institutions guaranteeing democracy, the rule of law, human rights and respect for and protection of minorities; a functioning market economy, as well as the capacity to cope with competitive pressure and market forces within the Union." Under Article 49 of the Treaty on the European Union, any European country may apply for membership if it meets a set of criteria established by the Treaty. In addition, the EU must be able to absorb new members, so the EU can decide when it is ready to accept a new member. Applying for EU membership is the start of a long and rigorous process. The EU operates comprehensive approval procedures that ensure new members are admitted only when they have met all requirements, and only with the active consent of the EU institutions and the governments of the EU member states and of the applicant country. Basically, a country that wishes to join the EU submits an application for membership to the European Council, which then asks the EU Commission to assess the applicant's ability to meet the conditions of membership. Accession talks begin with a screening process to determine to what extent an applicant meets the EU's approximately 80,000 pages of rules and regulations known as the acquis communautaire. The acquis is divided into 35 chapters that range from free movement of goods to agriculture to competition. Detailed negotiations at the ministerial level take place to establish the terms under which applicants will meet and implement the rules in each chapter. The European Commission proposes common negotiating positions for the EU on each chapter, which must be approved unanimously by the Council of Ministers. In all areas of the acquis, the candidate country must bring its institutions, management capacity, and administrative and judicial systems up to EU standards, both at national and regional levels. During negotiations, applicants may request transition periods for complying with certain EU rules. All candidates receive financial assistance from the EU, mainly to aid in the accession process. Chapters of the acquis can only be opened and closed with the approval of all member states, and chapters provisionally closed may be reopened. Periodically, the Commission issues "progress" reports to the Council (usually in October or November of each year) as well as to the European Parliament assessing the progress achieved by a candidate country. Once the Commission concludes negotiations on all 35 chapters with an applicant, a procedure that can take years, the agreements reached are incorporated into a draft accession treaty, which is submitted to the Council for approval and to the European Parliament for assent. After approval by the Council and Parliament, the accession treaty must be ratified by each EU member state and the candidate country. This process of ratification of the final accession treaty can take up to two years or longer. The largest expansion of the EU was accomplished in 2004 when the EU accepted 10 new member states. In January 2007, Romania and Bulgaria became EU members. Croatia formally joined the Union on July 1, 2013 bringing the Union to its current 28 member states. The EU has continued to support the enlargement process. Currently, there are five candidate countries; Montenegro, which was given candidate status in December 2010 and formally opened accession negotiations with the EU on June 19, 2012; Serbia which was granted candidate status in March 2012 and could begin actual negotiations by January 2014; Macedonia, which has a Stabilization and Association Agreement with the EU, but whose negotiations have been blocked by Greece and Bulgaria, and Turkey. Iceland, which began the accession process in July 2010 and opened and closed several chapters of the acquis has come under a new government which has reportedly told the EU Commission that it was no longer interested in pursuing membership in the Union. Prior to October 2009, in order for enlargement to continue, two barriers that existed had to be overcome. First, and although not explicitly stated, certain conditions established by the 2000 Treaty of Nice seemed to limit the EU to 27 members. In order for any other new country to be admitted to the Union, the Nice Treaty had to be amended or a new treaty ratified to allow further expansion of the Union. The Lisbon Treaty , which was agreed to in 2007 and took effect on December 1, 2009, permitted, among other things, future enlargement of the Union to continue. A second barrier to the current accession structure involves any candidate country whose accession could have substantial financial consequences on the Union as a whole. Under this provision, admission of such a candidate could only be concluded after 2014, the scheduled date for the beginning of the EU's next 7 year budget framework. Currently, only Turkey's candidacy would fall under this restriction although it is unlikely that Turkey would be admitted inot the Union within this 7-year timeframe. Turkey and the European Commission first concluded an Association Agreement (Ankara Agreement) aimed at developing closer economic ties in 1963. A key provision of that agreement was the commitment by Turkey to establish a customs union that would be applied to each EU member state. In 1987, Turkey's first application for full EU membership was deferred until 1993 on the grounds that the European Commission was not considering new members at the time. Although not technically a rejection of Turkey, the decision did add Turkey to a list, along with the United Kingdom, of nations to have been initially turned down for membership in the Union. In 1995, a Customs Union agreement between the EU and Turkey entered into force, setting a path for deeper integration of Turkey's economy with that of Europe's. In 1997, the Luxembourg EU summit confirmed Turkey's eligibility for accession to the EU but failed to put Turkey on a clear track to membership. The EU recognized Turkey formally as a candidate at the 1999 Helsinki Council summit but asserted that Turkey still needed to comply sufficiently with the EU's political and economic criteria before accession talks could begin. In February 2001, the EU formally adopted an "Accession Partnership" with Turkey, which set out the priorities Turkey needed to address in order to adopt and implement EU standards and legislation. Although Ankara had hoped the EU would set a firm date for initiating negotiations at the December 2002 EU Copenhagen Summit, no agreement was reached. Two years later, 10 new member states, including a divided Cyprus, were admitted into the Union. In December 2004, and despite the fact that Turkey had still not met its obligations regarding the application of its customs union to the EU member states, the European Council stated unanimously that Turkey had made enough progress in legislative process, economic stability, and judicial reform to proceed with accession talks within a year. In the aftermath of the Council's decision, the European Parliament voted overwhelmingly to support the Council's decision to move forward with Turkey. Although projected by many to require at least 10 or more years to complete the accession, the question of Turkey's membership in the Union became a debating point during consideration of the Treaty for a European Constitution in the spring of 2005. Many observers suggested that one of the factors contributing to the defeat of the Treaty in France and the Netherlands was voter concern over continued EU enlargement and specifically over the potential admission of Turkey, which was considered by many as too large and too culturally different to be admitted into the Union. Under a compromise formula agreed to by the Council, Turkey, before October 2005, would have to sign a protocol that would adapt the 1963 Ankara Agreement, including the customs union, to the 10 new member states of the Union, including the Republic of Cyprus. Turkey signed the Protocol in July 2005 but made the point that, by signing the Protocol, it was not granting diplomatic recognition to the Republic of Cyprus. Turkey insisted that recognition would only come when both the Greek and Turkish Cypriot communities on the island were reunited. Ankara further stated that Turkey would not open its seaports or airspace to Greek Cypriot vessels until the EU ended the "isolation" of the Turkish Cypriots by providing promised financial aid that at the time was being blocked by Cyprus and opened direct trade between the EU and the north. The decision by Turkey to make such a declaration regarding Cyprus immediately served to sour attitudes of many within the EU. In September 2005, the EU Council issued a rebuttal reminding Turkey that Cyprus was a full member of the EU, that recognition of all member states was a necessary component of the accession process, and that the EU and its member states "expect full, non-discriminatory implementation of the Additional Protocol to all EU member states ... and that failure to implement its obligations in full will affect the overall progress in the negotiations." The controversy over Turkey's accession continued until October 3, 2005, when, after a prolonged debate over the status of Cyprus and expressions of concern by some European member states over admitting Turkey at all, the EU Council agreed to a "Negotiating Framework," and opened formal accession talks with Turkey. However, the language of the Framework included an understanding that the negotiations would be open-ended, meaning an outcome (eventual full membership) could not be guaranteed. This language was to become a significant rallying point for some European governments such as Germany, France, and Austria, which proposed that Turkey be given a "privileged partnership" or some type of closer relationship with Turkey but one which fell short of full membership in the Union. For Turkey, 2006 became a difficult year in its relations with the EU even as formal negotiations between Brussels and Ankara began. The membership of Cyprus in the Union, despite the Greek Cypriot rejection of a U.N.-sponsored unification plan, and Turkey's public stance not to deal with the Greek Cypriot government, served to aggravate relations further and, in the opinion of some observers, may have contributed to the beginning of a change in attitude within Turkey and the EU toward each other. At the outset, Cyprus expressed its opposition to formally opening and closing the first of 35 negotiation chapters unless Ankara met its obligations to recognize all 10 new EU member states, including Cyprus.