Prime Minister Gordon Brown's office said on Monday he's determined to win approval for tougher anti-terrorism laws, which would give police the option of holding terrorism suspects in custody for 42 days before they are charged, or released.
Britain's House of Commons narrowly passed the plans in July. But peers in the House of Lords are likely to vote against them next week.
The proposal has caused divisions among police leaders. Some say the measure is needed because terror cases are complex - but others say they have enough power already.
Brown's office said Monday he'll press ahead. But a spokesman wouldn't say if Brown would invoke the Parliament Act, a law allowing him to bypass a no vote in Britain's House of Lords.