In the strongest comments yet by a minister, Kenneth Clarke said yesterday that Britain would not accept any change in the number of votes required to pass some decisions.
'The position we're in now, where two large member states and one small one can say they are not prepared to accept a decision against their national interests, is a perfectly satisfactory one,' said the Chancellor, in Brussels for a meeting of the Council of Ministers.
The issue has arisen because the entry of new states requires a change in the number of votes needed to pass legislation by a qualified majority. All but Britain and Spain want the ratio to remain at 70 per cent of the total.
'I don't accept there is any reason whatsoever to move to the 27- vote blocking minority which others seem to think automatically follows from enlargement,' said Mr Clarke.
At the moment 23 votes can block legislation, and Britain wants to keep it that way.
Officials said they did not necessarily expect agreement when foreign ministers meet in Brussels today. 'Sometimes agreement takes longer than we hope, and this may unfortunately be true again this week,' Douglas Hurd, the Foreign Secretary, said in Dublin yesterday.
Only Spain is close to Britain's line. The 10 other member states insist that the level of a blocking minority must rise to maintain existing EU rules.
There is a range of possible compromises, but none entirely acceptable to both sides.
A scheme that reflects the size of states would be extremely unpopular with small countries. 'Ireland is not prepared to accept any form of secondary weighting which is explicitly based on population size,' said Dick Spring, Irish foreign minister, in Dublin yesterday referring to what has been called the Spanish solution.
Another possibility is to delay decisions where two large countries are out of step and review the arrangement later, but it is unlikely that the Conservative Party or the European Parliament could stomach this.
If no agreement can be reached today, the issue will be discussed this weekend in Greece by foreign ministers. The row could drag on until the Corfu summit in June. This could delay the process of letting new members in, but it would also delay a decision until after the local and European elections, preventing any Tory split before then.
There will be intense pressure on Mr Hurd to settle today. Helmut Kohl, the German Chancellor, was due to contact John Major to impress on him the importance of a solution.
But while some Eurosceptic ministers remain intensely suspicious that a compromise could be imminent, indications in Whitehall were that Mr Hurdwould open today's negotiations in a tough mood.
With backbench hostility to a compromise extending far beyond the ranks of last year's Maastricht Euro-rebels, the threat of public dissent within the party in the run-up to the June European elections is a more immediate constraint for ministers than a Commons rebellion which could actually block European legislation.
Suggestions among Eurosceptic MPs that several ministers might resign if there was a climbdown were being treated with some caution in Westminster last night.
There were also growing indications that the Bill ratifying EU enlargement and the measure providing for an increase in EU contributions will be postponed until the 1994-5 parliamentary session.
Sir Edward Heath, the former Prime Minister, yesterday criticised Michael Portillo, the Treasury Chief Secretary who argued on Sunday that 'the British people believe that the Tories will defend British interests in Europe'.
Sir Edward Heath said that Mr Portillo 'does not seem to understand Europe, unfortunately'.
Inside Parliament, page 6
Price of failure, page 8
Leading article, page 15