Morris to warn rebellious teachers that strikes will put reforms at risk

Estelle Morris is to warn teachers today that they will damage their pupils' education and put school reforms at risk if they go on strike.

Ms Morris, the Secretary of State for Education and Skills, will speak at the National Union of Teachers' conference in Bournemouth as delegates prepare to vote on plans for further industrial action over pay, and moves to bring in private firms to run state schools.

Ms Morris will say threats of industrial action "make it more difficult to work together" on issues such as cutting teachers' workload. She will tell delegates: "Industrial action risks undermining the work we have done. It also damages the image of teachers in the public's mind and most of all it damages the pupil's education."

Ms Morris, who as an NUT member in Coventry in the Eighties went on strike over pay, now says she regrets the harm the action did to children. She will add: "Going back to the 1980s would be deeply damaging for pupils and teachers, so let me make it absolutely clear that you have a choice: It is going back to those old days or move forward."

An aide to Ms Morris said the heckling of Secretaries of State at previous teachers' conferences had damaged the image of teachers. However, he said the warning Ms Morris planned to deliver was not a threat that strike action could undermine talks with the Treasury over funding for reducing workload. Ms Morris is urging the Chancellor, Gordon Brown, as part of his comprehensive spending review, to approve the employment of 20,000 extra classroom assistants and give teachers guaranteed time for marking and preparation.

The aide said: "It's not a question of boo and you don't get the cash. It just muddies the waters if there are threats of industrial action and makes it more difficult to tackle some of the complex issues facing us. It makes it more difficult to justify to the taxpayer."

Ms Morris will be speaking against the background of threats from the three big unions – the NUT, National Association of Schoolmasters Union of Women Teachers and Association of Teachers and Lecturers – to ballot on industrial action if negotiations on workload fail this summer.

This weekend the NUT will debate calls for a strike over plans to bring in private firms to run schools, a move included in legislation going through parliament. Delegates say they will walk out if their pay or conditions worsen as a result.

The union will also debate a call for strike action, backed by its more moderate executive, over a claim for a 10 per cent pay rise, or £2,000, for the lowest paid teachers next year. Left wingers want further action over cost of living allowances in London and the Home Counties. NUT members staged a one-day walkout this month after they were offered a £105 rise in response to a demand for £1,000. Ms Morris will say the government cannot budge from the £105 recommended by the profession's pay review body.