Defeat looms on Social Chapter vote: Ashdown says Major's future in peril. Anthony Bevins reports

SENIOR MINISTERS believe that the Government will be defeated on Britain's Social Chapter opt-out when the Commons turns to the final stage of the Maastricht treaty legislation next Thursday.

After Commons questions in which John Smith and Paddy Ashdown prepared the ground for next week's clash, the Liberal Democrat leader said the result could determine John Major's survival as Prime Minister.

Mr Major was saying little - beyond giving MPs a clear indication that he would never sign up to the Maastricht treaty without his Social Chapter opt-out. Playing a dead bat, the Prime Minister told the Labour leader: 'We expect to ratify the treaty that I signed at Maastricht. The House has shown its support for the treaty. I expect it to do so again.'

That expectation was belied by the threatened alliance of Labour, Liberal Democrats and up to 40 Conservative rebels, who should have little difficulty in voting against a bland Government motion, tabled yesterday for debate on Thursday, that merely 'notes' government opposition to the Social Chapter. With an overall majority of 18 that can be overturned by just 10 Tory rebels, one of the few remaining doubts last night was over the votes of Ulster's 17 MPs.

However, it was said at Westminster that Ian Paisley and his two Democratic Unionist Party colleagues would certainly vote against the Government, as would the four SDLP MPs. In those circumstances, Sir James Kilfedder, Ulster Popular Unionist, and the nine-strong group of Ulster Unionists, led by James Molyneaux, could find it difficult to back ratification of a treaty they oppose - even if, as expected, ministers attempt to win their support with political inducements.

David Trimble, the Ulster Unionist MP for Upper Bann, told BBC Television's Westminster Live: 'We won't take a decision until Thursday morning. But as a party we went into the last election with a commitment against Maastricht, we've consistently voted that way through proceedings, and my firm expectation is that we will be supporting Nicholas Winterton (a Conservative rebel) and his friends when the time comes.'

Mr Ashdown told the same programme that a 'vacuum' would be created if the motion was lost - denying the Government the statutory basis on which to ratify the treaty. However, there was no reason for haste because the treaty was currently being challenged in the German Supreme Court, and that case would not be resolved until December.

'Even if we were to create a vacuum - in my view that is the most likely outcome - then the Government will have to think again and bring back to the House a resolution which can gain the support of the House,' he said. The vote could decide whether Britain had the Social Chapter or not, Mr Ashdown added. 'It could also decide whether Britain continues to have John Major as Prime Minister.'

That question is certain to be in the mind of many Conservative MPs at 6pm next Thursday - four hours before the crunch Maastricht votes - when Mr Major delivers his traditional end-of-term rallying call for unity and loyalty to the Conservative backbench 1922 Committee.

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