The House of Lords is expected to reject the controversial extension by an overwhelming margin when it votes today.

And former Shadow Home Secretary David Davis – who resigned as MP for Haltemprice and Howden to highlight the threat to civil liberties – said he did not believe Labour backbenchers would support using the Parliament Act to force it through.

"I think it will be dead," he told BBC1's Andrew Marr Show. "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.

"That was when 70 per cent (of the public) supported it, now it's about 30 per cent supporting the Government."

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

Labour backbencher David Winnick also warned that Gordon Brown was risking creating more divisions in his party by "foolishly" pushing ahead with the plan.

Forty-two renowned British writers yesterday added their voices to those attacking the extension of the maximum detention time from 28 to 42 days.

Those participating in the campaign – organised by human rights group Liberty – include 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 have been published online at www.42writers.com.

However, the Home Office insisted last night that it was determined to give police the "powers they need to tackle terrorism".

"It is not true that the Counter Terrorism Bill is to be dropped," a spokesman said. "The Government is determined to give the police the powers they need to tackle terrorism.

"That is why it is right and proper to legislate now to put in place the reserve power to go beyond 28 days if in future there is a clear operational need for it.

"We will now continue to press for these important measures as the Bill continues its passage through the House of Lords."

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