Landmark EU treaty comes into effect

Ireland ratified the treaty in October, the last country to do so

By Chris Morris BBC Europe correspondent

The Treaty of Nice, which paves the way for the enlargement of the European Union, has finally come into force.

The details of the treaty were agreed by EU leaders at a marathon summit in Nice in December 2000, but it then had to be ratified by every EU member state.

Prospective new members

Cyprus

Czech Republic

Estonia

Hungary

Latvia

Lithuania

Malta

Poland

Slovakia

Slovenia

Click here for an interactive map

Ireland submitted its ratification documents in December, the last country to do so.

That set 1 February 2003 as the date when the treaty becomes law.

The Treaty of Nice is long, complex and often confusing.

But without it, the European Union would not be able to add 10 new members to its ranks on 1 May next year.

What Nice does is to set out the institutional arrangements which will govern the new, enlarged EU.

It increases the size and some of the powers of both the European Commission and the European Parliament.

The commission will have 25 members -

up from 20.

The five biggest countries will no longer have two commissioners each.

Majority voting

The treaty also establishes a new system of voting in the Council of Ministers, setting out how many votes each country gets on all policy issues.

And it increases the scope of what is called qualified majority voting, allowing more decisions to be made by a majority of member states rather than by unanimous vote.

In other words, the treaty is supposed to ensure that the EU does not grind to a bureaucratic halt when the new members join.

The current President of the Commission, Romano Prodi, says Nice will allow the EU to function more effectively, but even he agrees that it is far from ideal, and it may soon be superseded.

The Convention on the Future of Europe, led by the former French President, Valery Giscard d'Estaing, is already working on a new constitutional treaty which could shake up the system far more radically.