Shadow foreign secretary David Miliband today accused the Government of sending out "mixed messages" over the UK's military mission in Afghanistan.
Labour leadership hopeful Mr Miliband accused Prime Minister David Cameron and Defence Secretary Liam Fox of "chasing newspaper headlines" over their comments about how long troops may remain in the country.
Mr Miliband said setting an "artificial deadline" for the withdrawal of the armed forces would create false hope in the UK and spur on the insurgents in Afghanistan.
His comments came after Dr Fox warned against any premature pull-out by international forces - saying it could jeopardise national security and would be a "betrayal" of those who had died fighting the Taliban.
The tone of Dr Fox's remarks contrasted with those of Mr Cameron who said at the weekend that he hoped to bring back the British forces by the time of the next general election, due to be held in 2015.
Mr Miliband told BBC Radio 4's Today programme: "It's essential in a war that a government provides clear leadership.
"We must say that the worst thing to do would be to leave only to have to send our troops back, that is the absolute worst thing."
He added: "I think it's very important that the mixed messages that are coming out from the new British Government are corrected very, very soon."
Mr Miliband said any decision on bringing troops home must be decided on the basis of the situation in Afghanistan.
"It's right that we do this on the basis of the conditions on the ground. To start setting artificial deadlines will give false hope to the British people and would give a false message to the insurgency.
"In fact, it would make it more difficult to get this political talks process finished. Because the absolute key to understanding this is to realise that a political process is not an alternative to military pressure. Military pressure makes it possible for the talks process to conclude.
"I say that the talks should be starting now, that the peace jirga that happened last month should have been far more wide-ranging and had far more support.
"I say that David Cameron and Liam Fox have to stop immediately saying different things. They seem to be, each of them, chasing newspaper headlines, they are sending mixed messages. I think that's very dangerous indeed."
Foreign Secretary William Hague yesterday insisted there had been no contradiction in what Mr Cameron and Dr Fox were saying.
"We are committed to the Afghans being able to conduct their military operations and security and that takes time. But I would be very surprised if that took longer than 2014," he said.
"Of course, in the next parliament he (Mr Cameron) would hope - anyone would hope - that the British combat troops were coming home. But he's also stressed that's not setting a timetable for what happens over the next few years."
Mr Miliband, in an open letter to new Nato commander General David Petraeus last month, said the peace process must involve the "vanquished as well as the victors".
He told Today: "I think it's essential that we use this period of military pressure and increased aid effort to create the conditions for a political settlement in Afghanistan. That is the only way in which this war is going to be won and ended.
"The preconditions for the end game are absolutely clear. Links with al Qaida have to be broken, all the tribes of Afghanistan have to be in and neighbours of Afghanistan have to be supportive.
"But I don't think there should be preconditions in the run-up to it.
"We have got to get this political process going because otherwise this is going to be a war that saps both the loyalty of the Afghan people and the will of publics in the West."
He added: "This has to be an Afghan-led process, it's not about us negotiating with the Taliban.
"This has to be about us being clear to the Afghan government it needs to lead a process that brings all the tribes of Afghanistan... inside the political process, working out a new balance of power at local level."Reuse content