Tony Blair is preparing for an emergency recall of parliament, probably next week once British forces have been ordered into action against terrorist networks in Afghanistan.

The prime minister is also expected to curtail his Labour party's annual conference, due to open on Sunday in Brighton. It was to have lasted five days but could be cut short after two, focusing on the crisis and allowing Mr Blair to make a rallying call to the nation. He prepared the country for the conflict on Monday by holding an unprecedented series of meetings with opposition leaders and senior MPs.

Iain Duncan Smith, the new leader of the main opposition Conservatives, was welcomed at the prime minister's official London residence. It was the first full meeting between the two, and is believed to be the first such one-to-one meeting with a leader of the opposition since the Falklands crisis.

Mr Duncan Smith said: "It is extraordinary times and extraordinary times require extraordinary things to happen. The reality is I think the British public expect the opposition to be loyal to them in this sense. If we are ever to defeat this threat of terrorism then we must stand with the government to do that."

Mr Duncan Smith declined to comment on the likely timetable. He and other MPs supported a recall of parliament, but only for a purpose such as endorsing a decision to send troops into action or to consider legislation. The prime minister's office was reluctant to say when a recall might happen, for fear of giving a signal of imminent action. It denied that Lieutenant General Anthony Piggott, deputy chief of the defence staff, who has just returned from Washington, had brought a firm US blueprint.

"We are still making assessments and fine-tuning options," Mr Blair's official spokesman said. It is expected that Britain will provide warships, aircraft and special forces for assaults against Osama bin Laden and terrorist networks in Afghanistan.

Mr Blair also spoke to Charles Kennedy, leader of the smaller opposition Liberal Democrats, on Monday. Mr Kennedy warned there were limits to the support he would offer, and said troops should be used only if Britain was involved in planning and risk assessment.

Later, in an emergency statement to the party's annual conference at the south-west England resort of Bournemouth, Mr Kennedy said he had talked to the prime minister about "the need to balance legislation with the interests of domestic civil rights".