He added that the Labour front bench would vote for British participation in the treaty's social chapter - on which John Major had got an opt-out - because he had been assured that a Commons victory on that issue would not wreck the treaty or the Bill. But Labour would not vote for some of its own amendments if they threatened the treaty's survival.
Although the Shadow Cabinet has yet to take a formal decision, Mr Cunningham's statement shut the option, carefully left open by John Smith late last year, that Labour might oppose the Commons final, third reading of the Maastricht legislation, expected around Easter.
Last year, the open option helped to heighten government uncertainty and maintained delicate Shadow Cabinet unity. But Mr Cunningham told the Independent last night: 'I do not want to see the Maastricht treaty defeated. I have never made any secret of that.'
At a private Parliamentary Labour Party meeting last week, Mr Cunningham flatly rejected a suggestion that the party should vote for all of its own amendments - even if they threatened to wreck the treaty and the Bill. 'Some of those amendments are down simply to secure a debate on important issues,' he said. 'But we know they are wrecking amendments and we are not going to fall into the trap of voting for them willy-nilly. It is not my intention to wreck the Bill at all.'
Earlier, during the eighth day of the Commons committee stage examination of the treaty legislation, Mr Cunningham clashed with Tristan Garel-Jones, the Foreign Office minister, over the consequences of a government defeat on the social chapter - for which some Tory rebels are threatening to vote.
Mr Garel-Jones appealed to Liberal Democrat and pro-EC Labour MPs to vote against any Opposition move to reverse the opt- out. Just back from Bonn, Mr Cunningham said he had been told by German ministers that a British U-turn on the social chapter would not be a problem for the other 11 EC members. 'If we win the vote on the social chapter,' he added, 'the Government can include it in the treaty with no threat to the Bill at all.'