More than 30 primary, secondary and nursery schools in the region will close completely as teachers up and down the country will be taking part in the first national strike for more than 20 years in protest at the government's proposed pay rise of 2.45%.

But the National Union of Teachers (NUT) claims this amounts to a below-inflation pay increase.

Many secondary schools will be partially open to pupils in years nine and 11, who are preparing for exams in just a few weeks' time.

Some headteachers also warned parents before the Easter break that their school would be closed so they could make childcare arrangements.

Southlands High School in Chorley is among those that will be closed as more than 50% of staff will be taking part in the action.

Mark Fowle, headteacher of Southlands, said: "All our teachers are not in the NUT but over half of the staff are.

"The rest of the teachers will be in as normal but we have decided to close as it would be very difficult to fulfil our timetable with so few staff."

Ashton Community Science College will also be closed for lessons. A spokeswoman said: "One third of our teachers are NUT members so lessons have been cancelled on Thursday.

"However, the rest of the staff will still attend work and there will be no picketing outside school."

But some schools, including Brownedge St Mary's Catholic Sports College in Bamber Bridge, Winmarleigh CE Primary near Garstang and Greenlands Primary School in Ribbleton, will be open as usual.

Julie Bolton, headteacher of St Lawrence CE Primary School in Barton, said: "Only one of our members of staff will be taking part in the action, so we are open as usual.

"Most of our staff are not members of the union involved."

County Coun Vali Patel, cabinet member for schools, said: "It is unfortunate that the situation has reached the point where teachers' unions feel that industrial action is unavoidable with the disruption to schools that inevitably follows.

"In the event that a school has to close, it will be the parents' responsibility to look after their children, as they would on any other day they were out of school."

Schools minister Jim Knight said: "I am disappointed by the decision to strike, as I think parents will be - and as will the majority of teachers who did not vote to strike.

"We believe that all teachers should be teaching and talking - and not walking out."

Schools will not be picketed by the striking teachers, but NUT members from across the county are expected to attend a mass protest rally at Preston North End's Deepdale ground from 2pm.

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