The pupils, who are between the ages of five and nine, attend Cookridge Primary School in Leeds.

Leeds City Council wants to close the school on the grounds that it has too many empty places.

But papers lodged in the High Court on behalf of the 20 children argue that the authority has failed in its duty to consult over a proposal which has been made on the basis of out-of-date information.

The legal campaign against closure is being led by solicitor Jonathan Cairns, who has a child at the school.

The school has 273 pupils on its roll

The headteacher of Cookridge Primary, Stuart Tomlinson, said: "We have a very determined group of parents and governors at the school who are going to explore any avenue to prevent this closure.

"The council wants to move the children to another school, but parents are saying they won't do that."

Mr Tomlinson says the council assumes the school has places for 420 children, but that the conversion of classrooms for projects including a library and homework club have reduced this number to 327.

"There are currently 273 children on the roll, but we have lost around 60 pupils since the closure decision was made," he said.

Cookridge Primary's last inspection report, published in 1995 by the Office for Standards in Education, described it as "a good school with some very good features".

A spokeswoman for Leeds City Council said: "We feel it was inappropriate of the school to take legal action at this stage.

"No decision has been made to close Cookridge Primary School.

"A period of public consultation has been held, and individuals and organisations now have until 2 November to submit formal objections to the proposals."