LORD Phillips of Worth Matravers, the most senior judge in England and Wales, has warned that overcrowding in prisons is now "critical".

The Lord Chief Justice warned: "We simply cannot go on like this."

Lord Phillips added said the government had not "fully appreciated" the impact of introducing laws in 2003 which forced judges to impose longer sentences.

In a speech to an event organised by the Howard League for Penal Reform in the City of London, Lord Phillips said: "Unless parliament is prepared to provide whatever resources are necessary to give effect to the sentences that judges choose, in their discretion, to impose, parliament must re-examine the legislative framework for sentencing.

"I do not believe that these simple propositions have been fully appreciated by those responsible for formulating criminal policy to which parliament is invited to give effect."

He added: "The scale of sentences is now largely determined by parliament. Where, within that scale, the facts of a particular offence fall is the judge's task. Parliament should, when altering that scale, have regard to the resource implications of the changes that are proposed."

Describing the impact of the record jail population, the judge said: "We are at present in a critical situation."

Some of the consequences of the 2003 Criminal Justice Act - which led to longer sentences for murder and a range of other serious crimes - appeared not to have been foreseen by the government, he said.

"If you decide to lock up one man for a minimum term of 30 years, you are investing £1 million or more in punishing him," he said.

"That sum could pay for quite a few surgical operations or for a lot of remedial training in some of the schools where the staff are struggling to cope with the problems of trying to teach children who cannot even understand English."

He told the audience of the event that he hoped the forthcoming report on jails by government trouble-shooter Lord Carter of Coles would trigger a public debate on linking sentencing with funding.