The Government's controversial plans to increase the terror detention limit to 42 days will be effectively killed off by a defeat in the Lords, one of the measure's leading critics has said.

Peers will vote on increasing the pre-charge custody time limit for terror suspects from 28 to 42 days on Monday.

Former shadow home secretary David Davis, who resigned as an MP to force a by-election over the Government's record on civil liberties, said: "I think it will be dead.

"I think it will be thrown out by a huge majority."

He said the measure, contained in the Counter-Terrorism Bill, no longer had support from the public and the Government would not have the political will to force it through using the Parliament Act to overrule the House of Lords.

The Tory MP said: "It was something that was profitable for the Government - they thought by having 42 days and us opposing it they would make us look weak and them look strong."

He added: "That was when 70 per cent supported it, now it's about 30 per cent supporting the Government."

He continued: "Their own party probably won't support them in the Parliament Act, so I think it's probably over."

Gordon Brown narrowly got the measure through the Commons by just nine votes in a major test of his authority in June.

Mr Davis shocked Westminster by standing down as MP for Haltemprice and Howden in protest at the result and was re-elected after a campaign designed to highlight what he described as the "erosion" of civil liberties under Labour.

More than 40 renowned British writers have also joined forces to attack the government over its detention plan.

The list of writers taking part in the campaign, co-ordinated by human rights group Liberty, includes illustrious names such as Philip Pullman, Monica Ali, Julian Barnes, Ian Rankin, Alain de Botton, Ali Smith and AL Kennedy.

Each writer has produced a new piece of work lambasting the controversial legislation, which will be published online at www.42writers.com.

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