Brown plans to appeal directly to his MPs over 42 days detention

Gordon Brown is expected to make a direct appeal to Labour MPs for their support on the controversial 42 days detention plan contained in the anti-terror bill. He is expected to do it on Monday night at the regular meeting of the Parliamentary Labour Party. Jacqui Smith, the Home Secretary, is due to speak to the PLP in room 14 at 6pm but Brown allies say that the PM is considering elbowing her aside.

It is the first PLP meeting since the Crewe and Nantwich by-election and Smith's allies at the Home Office have been preparing the ground for a minor climbdown over Brown's insistence that the Commons approves an extension of detention without charge from 28 days to 42 days for terrorist suspects. Ms Smith has signalled she will table amendments next week to the anti-terror bill that will halve the period during which the police can enact emergency powers from 60 to 30 days.

Under these plans Smith would have to come to the Commons within two days of announcing an emergency - for example after a bomb on the Tube. At the moment, the police would have 60 days during which they could trigger the power to hold a suspect for 42 days without charge. But under the amendment, the police would only have 30 days to trigger this reserve power.

Shami Chakrabarti, the director of Liberty, the civil rights campaign opposing the plan, has accused the Labour whips of using dirty tricks to try to beat down the number of potential rebels, accusing them of falsely telling Labour MPs in private that she is prepared to compromise. In an angry letter to Labour MPs denouncing their tricks, she says: "I understand that the Whips have been briefing that Liberty is willing to negotiate or compromise on 42 days. This is completely untrue - our position remains unchanged.

"Liberty will not be auctioning off our hard-won rights and freedoms in exchange for the promise of last-minute and meaningless safeguards. This issue is too important and we have worked too hard to win the support of you and your colleagues."

So far, the Labour MPs appear to be resisting the pressure to auction off their rights. Home Affairs select committee chairman Keith Vaz said the concessions were welcome but did not go far enough. But that could change on Monday night.

Brown knows the Government cannot afford a defeat at the hands of his own MPs. But he is now in the extraordinary position of being so weak that they may back off, rather than see him humiliated again.

THE MOLE: ANTI-TERROR BILL

LAST UPDATED 1:27 PM, MAY 30, 2008