The Conservatives obtained data showing police cells were used 60,953 times last year compared with 4,617 in the previous 12 months, at an average cost of £385 a night.

Shadow police reform minister David Ruffley said widescale use of police cells to house inmates amounted to "incredible ministerial incompetence".

"This means police stations are being clogged up and police time wasted," he said. "Government incompetence means police are spending more time as prison jailers and less time as crime fighters.

"There have been huge increases in the number of prisoners being kept in police cells in all but two out of the 42 police forces."

In the Metropolitan Police area, the number of occasions where prisoners were held in police cells under so-called "Operation Safeguard" soared from 333 in 2006 to 9,799 in 2007.

In the Kent they were used 3,292 times compared with 335 in 2006, while in West Yorkshire the figure rose from 45 to 3,432 days.

Mr Ruffley said: "In 2006, 18 police forces didn't have to keep any prisoners in their police cells but in 2007 every single police force has had to look after prisoners. Police budgets are being hit hard by this incredible ministerial incompetence."

A spokeswoman for Prime Minister Gordon Brown said: "We are aware of the statistics that have been put out today by the Ministry of Justice reflecting Operation Safeguard which was using police cells as prison accommodation. This is something that is being actively looked at at the moment by the National Offender Management Service (Noms)."

She added that the proposed building of new "Titan" prisons holding up to 2,500 inmates - as recommended by a review published at the end of last year - was designed to "alleviate the current situation".