School truancy levels should remain a serious concern for the government, according to an auditors report published on Friday.

The National Audit Office research found unauthorised absence from the classroom remains at 0.72 per cent, despite the spending of £885 million on anti-truancy measures since Labour came to power in 1997.

In total 450,000 of the 6.7 million state school pupils are absent on an average day, although most of these are due to authorised sickness.

The NAO said that with absence rates varying widely between schools, best practice should be spread through local authorities, while a new emphasis should be put on encouraging a good attendance culture in primary schools.

"Attendance needs to be managed because, while absent, young people are not benefiting from education to the value of £1.6 billion each year," the report from parliament's spending watchdog concluded.

Meanwhile, head teachers have claimed a third of councils are "short-changing" primary schools by withholding money from their budgets.

The National Association of Head Teachers Schools said many schools were losing enough to pay for two extra teachers.