The only teachers’ union not to sign the workload agreement could be on its way to seeking a truce with the Government, after Doug McAvoy, its general secretary departs this summer.

Mr McAvoy, at his last conference as leader of the National Union of Teachers, used his speech in Harrogate to give a double-barrelled blasting to the Government and other teacher unions. But the signs are that his potential successors are keen to come in from the cold where the union has been consigned by ministers.

Supporters of Steve Sinnott, Mr McAvoy’s deputy and one of the favourites to win the leadership contest, believe the whole political climate will change if their man wins in June and that Mr Clarke will attend the 2005 NUT conference in Gateshead after two years of pointed snubs. Senior Labour politicians and figures within the trade union movement are already understood to be lobbying for a rapprochement. The Government will not want to risk an escalating war with the NUT in the run-up to a general election likely to be fought on public services issues.

While Mr Sinnott and the contest’s other frontrunner John Bangs, NUT head of education, made unequivocal commitments not to sign the agreement last weekend, both are unhappy at being in a situation where ministers will only consult them when they have to by law.

Last week Brendan Barber, Trades Union Congress general secretary, told the Association of Teachers and Lecturers’ conference in Bournemouth that he supported the workload deal and voiced his “deep regret” that all the unions had not been able to agree on it.

Ministers are aware of the internal pressures that the new general secretary will be under and will not want to endanger a possible fresh start by forcing the issue on a document that will be 18 months old by the time the new leader takes up his post.

And despite tough talking by its activists, the NUT has found it very difficult to mount effective industrial action against a deal designed to reduce its members’ workload. Its one attempt at Radclyffe school, Oldham, failed.

Mr Bangs, as Mr McAvoy’s favoured candidate, might find it more difficult to rekindle relations with the Government, having been closely associated with the current stand-off. But he is not as aggressive as Mr McAvoy and does want to talk, although he plans to press his case by warning of the trouble that the NUT could make for the Government if it does not behave more reasonably.

Ian Murch, like his colleague from the left, Martin Powell-Davies, is strongly opposed to the Government on many policies but still hopes to make more progress by adopting a less abrasive style than Mr McAvoy.

That style was in full evidence on Tuesday as the outgoing general secretary used his last conference speech to mount another all-out assault on New Labour education policy. “The Prime Minister wants schools to be run like Tesco stores,” Mr McAvoy said, later getting a standing ovation.

He also attacked the other main teaching unions for their betrayal, and the TUC for its “deplorable” decision to promote the workload agreement.

* The Sinnottite Broadly Speaking faction on the NUT’s national executive lost ground in the committee chair elections for the first time in 30 years, with six of the 18 positions going to independent and left-wing members.