A number of schools in the district could be disrupted tomorrow while the two largest teaching unions hold a one-day strike over pay, pensions and working conditions.

Unless agreement is reached, the NUT and NASUWT are planning to take action as part of a wave of regional strikes, which is likely to result in the closure or partial closure of some primary and secondary schools in St Albans and Harpenden.

Chris Hayward, Herts County Council’s cabinet member for enterprise, education and skills, said: “While we recognise that there are strongly held feelings on both sides of this national dispute, strike action in a key public service like this can only be to the detriment of Hertfordshire’s children and their parents.

“We hope that there is a speedy resolution to this dispute in the interests of all concerned.”

He added: “The decision to stay open or to close is for individual school head teachers and governors to make. We have urged as many schools as possible to remain open as long as it is safe to do so but we do not have any authority to compel them to stay open, whether they are community schools, free schools or academies.

“If school leaders do decide to close their doors, we have advised them to inform parents and carers as soon as possible in advance so that they can make alternative arrangements for their children.”

The council has advised parents to contact their children’s schools directly to find out about closures as individual schools are not obliged to provide them with information so they cannot give an “entirely accurate” picture.