|PIC1|Thousands of schools will be forced to close on Thursday as teachers stage their first national strike in 20 years, in a dispute with the government over pay.

Up to 200,000 members of the National Union of Teachers will take part in the one-day action in protest at a three-year pay deal announced in January.

"Teachers do not take the decision to strike easily, or lightly, but teachers' patience has been stretched to the limit," said Christine Blower, the NUT's acting General Secretary.

"This is not just a one year issue. After three years of below-inflation pay increases, the prospect for a further three years of the same is the last straw."

The pay deal, recommended by the independent School Teachers' Review Body, would see salaries rise by 2.45 percent from September 2008, and by 2.3 percent in September 2009 and 2010.

"I think it is very regrettable that the teachers are going on strike tomorrow," Prime Minister Gordon Brown told MPs on Wednesday.

"The reason is that even the chairman of the pay review body has said this is an independent award, independently adjudicated, one that the teachers should be prepared to accept.

"I hope that after reflection the teachers will reconsider the action that they are going to take in the future on this matter."

The Local Government Association said more than one in six schools would be affected, according to a survey of 91 councils. It said 1,896 schools would be shut all day with another 2,006 partially closing.

It is the first time that teachers across the country will be striking for 21 years.

"It is disappointing for children and parents that the NUT has pressed ahead with strike action," said Councillor Ivan Ould, chairman of the National Employers' Organisation for School Teachers.

"Children so close to their exams will lose out on invaluable study time and parents will lose out as they are forced to take unnecessary holiday to look after them."

Just over 75 percent of NUT members backed industrial action over the pay increase and the union said it was expecting strong support for the strike.

However, other major unions such as the NASUWT and the Association of Teachers and Lecturers will not be striking, as they have argued that teachers had done better than other public sector employees.

Millions of workers paid by the government have expressed disappointment and frustration at their latest pay awards, most notably police officers, with thousands marching through London to protest at the decision not to backdate their pay rise.