ONE of Tony Blair’s closest political allies, Lord Falconer, has pledged to lead the Lords revolt against Gordon Brown’s flagship antiterror measures, if MPs back the prime minister this week.

On the eve of the knife-edge Commons vote on plans to extend detention without trial to 42 days, the former lord chancellor warned that the bill was “unacceptable”.

Falconer, who was once Blair’s flatmate, said that ministers’ concessions adding new legal safeguards had not gone far enough. “It doesn’t look like the amendments quite do the job,” he said last night.

Brown was this weekend planning further concessions to appease Labour rebels who fear that innocent people could be detained.

Ministers are set to agree to rebel demands of financial compensation for terrorist suspects detained under the 42-day provision but later released without charge.

Innocent detainees would be entitled to claim up to £3,000 for each day spent in jail, under the proposal being considered by No 10 this weekend.

MPs representing Muslim communities warn that anyone detained under the antiterror measures would see their reputations and careers destroyed because of the inevitable publicity that would surround their case.

Mohammad Sarwar, Labour MP for Glasgow Central, said: “I am concerned that some people are held for 42 days and let out without charge. There has to be a compensation package.” Khalid Mahmood, MP for Birmingham Perry Barr, said: “If a mistake is made it is important that compensation is available. This would provide an added safeguard.”

Falconer’s opposition to the legislation will stiffen the resolve of critics in the Lords. The former cabinet minister was one of the architects of Blair’s earlier, more draconian plan to hold terrorism suspects without charge for up to 90 days, which was rejected by MPs.

However he believes that an “artificial” limit is no longer needed because the threshold for when charges can be brought has been lowered.

“If we win narrowly in the Commons we have to accept that our chances of pushing it through the Lords are now close to zero,” said a senior Labour figure in the Lords. “There is heavyweight opposition on all sides.”

If Brown fails to win over the rebels and suffers a Commons defeat, the future his own leadership will inevitably come under the spotlight.

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