Westminster education authority said Mr Straw sought and received permission from Pimlico School for his daughter Charlotte to miss the first five days of term because of a family holiday in India.

The situation contrasts with the furore surrounding the Tony Blair's holiday in the Seychelles, which has led to his three children missing the start of term.

Downing Street has insisted that the Blairs informed the London Oratory School of their holiday arrangements, but its headmaster, John McIntosh, described the absence of Euan and Nicky Blair on the first day of term as "unauthorised".

Kathryn Blair has missed the first two days at St Joan of Arc Primary School, in north London.

'Hypocrisy'

Teachers' unions and political opponents have accused the prime minister of "hypocrisy". Only recently, the Education Secretary, David Blunkett, supported teachers' leaders who criticised parents for taking their children out of school on unauthorised leave.

Parents are allowed to remove their children from school for 10 days a year outside school holidays, but only with the express permission of the headteacher.

Pimlico School has refused to comment on the Straws' holiday arrangements, but a spokesman for Westminster education authority said five days' leave for Charlotte, an A level student, was agreed well in advance.

"Mr Straw approached Charlotte's head of year and the school's head teacher, Philip Barnard, and this arrangement was considered and agreed well in advance."