The draft Convention has rekindled claims in Britain that the EU is set to become a centralised political union. The Conservatives yesterday demanded a referendum on the plans, with the Shadow foreign secretary, Mr Michael Ancram, claiming they would erode seriously Britain's ability to manage its own affairs.
The Welsh Secretary, Mr Peter Hain, the government's representative on the convention, dismissed calls for a referendum and accused the Conservatives and some in the media of trying to "frighten" the public by misrepresenting the constitution as a threat to British sovereignty.
The draft unveiled in Brussels would, if approved, commit member-states to "unreservedly" backing an EU common foreign policy. It says the EU shall in future have "legal personality" and incorporates a legally binding charter of fundamental rights, including labour and social policies.
Despite the fact that the text drops the word "federal" - apparently at the insistence of the British prime minister, Mr Tony Blair - and leaves out any reference to earlier plans to change the EU's name to "United Europe" or "United States of Europe", there is still plenty for Eurosceptics to get their teeth into.
For any new treaty to be implemented, there will have to be unanimous agreement among the member-states - ensuring, as Mr Blair keeps pointing out, that anything unacceptable to Britain can and will be blocked.
Mr Hain said: "Europe will remain a union of sovereign nation states with governments such as Britain's in charge. By deleting the word 'federal', it is a clear signal that the rest of Europe shares Britain's views.
"There will be no harmonisation of tax. Governments will remain in charge of foreign and security policy with countries like Britain having a veto in the future."
Mr Ancram said in a statement: "This is very much as we feared. It is not a tidying-up exercise. It is a step-change away from the partnership of nations, which is what Europe should be, towards a political union with its own president, its own foreign secretary, its own constitution."