The European Union, or EU, describes itself as a family of democratic European countries, committed to working together for peace and prosperity

European Union

History

Maastricht and beyond

Key issues

Reform treaty

New presidency

Supporters of enlargement view it as the best way of building economic and political bonds between the peoples of Europe in order to end the divisions of the past.

They look forward to sharing the world's largest single market and so to expanding and consolidating stability and prosperity.

Critics highlight the fact that average GDP per head for the new member states is 40% of the average for existing EU countries, making them an economic burden.

Some also contend that the EU decision-making process will become bogged down as the number of countries round the table increases.

Fears have been expressed in some quarters that established EU members will see a huge influx of immigrants from former communist states seeking better job and benefit prospects.

The response from supporters of enlargement is that new talent is to be welcomed - and that immigration is unlikely to occur on a large scale as most people will want to stay put.

In the short term, existing members are allowed to limit employment rights for people from new member states.