Any European country which respects the principles of liberty, democracy, respect for human rights and fundamental freedoms, and the rule of law may apply to become a member of the Union. The Treaty on European Union sets out the conditions ( article 6, article 49).
Applying for EU membership is the start of the long and rigorous process. The official starting point is that a country submits an application - although this invariably arises out of an already strong bilateral relationship with the EU. A valid application triggers a sequence of EU evaluation procedures that may - or may not - result in a country eventually being invited to become a member. The speed with which each country advances depends solely on its own progress towards our common goals.
The application from a country wishing to join is submitted to the Council. The European Commission provides a formal opinion on the applicant country, and the Council decides whether to accept the application. Once the Council unanimously agrees a negotiating mandate, negotiations may be formally opened between the candidate and all the Member States. This is not automatic, though. The applicant country must meet a core of criteria before negotiations start.
The so-called " Copenhagen criteria ", set out in December 1993 by the European Council in Copenhagen, require a candidate country to have:
In 1995 the Madrid European Council further clarified that a candidate country must also be able to put the EU rules and procedures into effect. Accession also requires the candidate country to have created the conditions for its integration by adapting its administrative structures. While it is important for EU legislation to be transposed into national legislation, it is even more important for the legislation to be implemented and enforced effectively through the appropriate administrative and judicial structures. This is a prerequisite of the mutual trust needed for EU membership.
In addition, the EU must be able to integrate new members: it needs to ensure that its institutions and decision-making processes remain effective and accountable; it needs to be in a position, as it enlarges, to continue developing and implementing common policies in all areas; and it needs to be in a position to continue financing its policies in a sustainable manner.