TENS of millions of pounds of taxpayers' money are being wasted each year on nearly 800,000 "empty desks" in schools.

According to government figures, nearly one in seven primary schools and one in 10 secondaries are at least a quarter empty, their pupil rolls slashed by falling local birth rates or parents choosing better schools further away.

Areas with the most surplus school places range from rural counties such as Kent and Norfolk to inner-city areas such as Knowsley on Merseyside.

With government spending on schools likely to be reined in after the recession, pressure is likely to grow for a "cull" of empty places in primary schools in sparsely populated areas and in unpopular comprehensives.

"Many areas are going to be facing some very difficult decisions as primary school numbers continue to fall," said David Laws, the Liberal Democrat schools spokesman, who obtained the figures in a Commons written answer. They cover the period 2001-7.

"With this number of secondary school surplus places, it is also clear many parents are rejecting their most local school."

Alan Smithers, education professor at Buckingham University, said politicians were reluctant to reduce surplus school places, despite the expense of keeping them open.

"The corollary of parental choice is supposed to be that parents move their children away from poorly performing schools and that those schools eventually go out of business, raising standards across the system," said Smithers. "At the same time local communities are very attached to their schools and politicians are after their votes." The area with the highest proportion of empty secondary school places is Hackney, east London, where 22% are surplus to requirements. In Wakefield, West Yorkshire, 21% of primary places are unfilled.

Another badly affected area is Kent, where the number of primary schools at least a quarter empty nearly doubled from 44 to 80 between 2004 and 2007. In the past year, the council has closed about five schools and amalgamated others.

Those whose pupil rolls have been falling include Cranbrook Church of England primary school near Tunbridge Wells, the register has dwindled from about 400 six years ago to just 215 today.

Peter Wibroe, 52, the headteacher, said: "In times of financial uncertainty I believe people will be less inclined than ever to have children, or move to areas like this with their families and boost the intake at small schools.

"We have had to adapt very quickly. When I started two years ago, there were 10 classes. Now we have just eight."

Local authorities contacted over the figures said they were keen to avert school closures wherever possible. Some pointed out that it was advisable to retain surplus places because pupil numbers were set to begin rising again after years of decline.

The Department for Children, Schools and Families said funding announced in November's pre-budget report by Alistair Darling, the chancellor, for building new schools could be used to reduce surplus places, for example by removing temporary accommodation in cabins. She added: "Closing schools is a drastic last resort."

Click here to see how many empty school desks there are in your area: figures for 2001 to 2007

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