The government's Prevention of Terrorism Bill continued to shuttle between the Commons and the Lords as the papers went to press last night.

Peers continued to refuse to back down in their opposition to the planned control orders for suspects.

The two remaining sticking points were the issue of a sunset clause in the legislation and the standard of proof required to issue a restriction of liberty.

Having accepted some concessions, home secretary Charles Clarke stuck to his guns with the backing of the prime minister.

Clarke angered opposition parties by claiming that weakening the bill would "encourage terrorists to locate in Britain".

Meanwhile an Algerian national was released from Belmarsh high security jail yesterday having been held without trial or charge under the previous legislation for more than three years.

Metropolitan Police commissioner Sir Ian Blair entered the debate by saying it would be a "great threat to national security" if Belmarsh detainees were released without replacement powers.

However Conservative leader Michael Howard said: "I don't think it is in Britain's best interests for this bill to become law permanently... if he [Tony Blair] is serious about fighting terrorism he will accept that."