Why does the EU need a new treaty?

The EU wants to update its rules after expanding from 15 to 27 members. An EU Constitution was drawn up in 2004 but rejected by French and Dutch voters in referendums in 2005.

What is in the treaty?

The EU will gain its own foreign minister (known as the High Representative) and a full-time President of the European Council (the post currently revolves between member states every six months). The European Commission will be cut from 27 commissioners to 18. A Charter of Fundamental Rights will guarantee social and employment rights. Countries will lose the right to veto justice and home affairs policy which becomes subject to qualified-majority voting (QMV). The EU will gain "legal personality" so it can sign international treaties in its own right. QMV will be extended into 50 areas of policy-making.

How does it differ from the EU constitution?

It differs in format: the treaty amends previous treaties rather than replacing them in a single new document. It also differs slightly in content: references to the EU's anthem and flag have been removed, although no-one expects the EU's blue flag with gold stars to disappear.

Weren't we promised a referendum?

Tony Blair promised a referendum on the Constitution which Labour confirmed in its 2005 manifesto. Gordon Brown now argues that the different style of treaty combined with British opt-outs mean the treaty need only be ratified by MPs not the public.

What are the British opt-outs?

Britain has secured the ability to opt in to new EU policies on justice and home affairs on a case by case basis and it has a protocol disapplying the Charter of Fundamental Rights to stop it being used to change British law. The Government insists that these measures will meet four "red lines" to protect British sovereignty in: labour and social legislation; the common law system, police and judicial process; foreign and defence policy, including Britain's seat on the UN Security Council; and any change to the "cost, scope and financial structure'' of the social security system.

What happens next?

EU leaders are expected to sign the final version of the treaty in December. The national ratification process will take place during 2008 with the aim of bringing the treaty into force on January 1 2009. On that date, the EU wants to appoint its new High Representative for Foreign Affairs and the President of the European Council.

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