Threat of delay for would-be members: Andrew Marshall in Brussels considers the consequences if the Twelve fail this week to agree on post-enlargement voting rules

IF THE European Union cannot agree on new voting rules this week, it is increasingly unlikely that new members will be able to join at the beginning of next year, Commission officials said yesterday.

The 1 January 1995 was set as the date when Sweden, Finland, Austria and Norway would enter, as long as their national electorates agreed. But the timetable is slipping now and the middle of next year is starting to seem more likely.

If Britain is seen to be the state that blocks enlargement it will suffer the wrath of the other states. The Government insists that it is intent on avoiding this. 'We are in favour of enlarging the Union,' said Kenneth Clarke yesterday. 'We do not accept that it automatically follows from that that we have these institutional changes.'

Agreement is still possible. If foreign ministers fail to agree today on the EU's post-enlargement voting system they will in any case meet this weekend in Greece. If they fail again, ministers and heads of government will have to think again. There is reluctance to hold a special EU summit. Agreement could then be reached at the Corfu summit but 'that would be very late', said a German spokesman yesterday.

The European Parliament must agree on enlargement before referendums can go ahead in the applicant states. There are European elections in June; and even if there is agreement this week among ministers, it may be hard to get Parliament to vote it through before the end of the May session.

An absolute majority of votes - 260 out of 518 - is required. Many deputies are not returning after the June elections, and hence will not be in Strasbourg for the next two sessions, or are campaigning. If not enough turn up, or if a few vote against, enlargement could fail.

Each applicant plans a referendum. Sweden will vote on 13 November. Opinion there is running against membership and the result is in doubt. Opinion in Austria is also opposed at the moment, and in Norway it seems unlikely that a 'Yes' vote is possible. But Finnish opinion is in favour.

If the deal does not go to Parliament until September, or even October, then the Swedish referendum could still go ahead. But all 12 national parliaments must also ratify enlargement. The deal will, like the Maastricht treaty, contain a provision that it enter into force after all countries have approved it.

If the new states cannot be in the EU by January 1995, then when? One possibility is that the date would go back six months, and this, Commission officials were saying even before the present row, would be no disaster. The date that really matters, they say, is 1 January 1996, when the EU begins a new round of talks on changes to its internal rules - a re-run of the Maastricht negotiations. That will again raise complex issues about new voting requirements: in many respects, the present row is just an overture.