Doug McAvoy, who is seeking re-election as general secretary of the National Union of Teachers, has accused his rival, Christine Blower, of using the union as a means of pursuing an extreme left-wing agenda.

Throughout the campaign Christine Blower has rejected such claims, saying that she would represent the interests of teachers and was not "controlled" by any "extreme organisation".

Christine Blower says she is not representing any "extreme organisations".

In her campaign to oust the current general secretary, Christine Blower has promised to "lift the unreasonable burdens on teachers, to ensure we are decently paid and that our views on education are heard and respected".

But with only two full days of voting remaining, Mr McAvoy says that the union could be "sleepwalking" into a take-over by extremists who want to put the union onto a collision course with the government.

If his opponent wins the election, Mr McAvoy claims that "the union will become more confrontational. There will be more disruption in schools and the union's image and stature will be adversely affected".

Seeking to mobilise the moderate vote, Mr McAvoy says that Christine Blower's supporters were well organised and would be working hard to get out their vote. These activists had already taken over half of the union's local associations, he said.

Appealing to those members who do not usually vote, Mr McAvoy says that if he was defeated the union would change in character, adopting a confrontational stance which would not be to the liking of a majority of teachers.