The Prime Minister has already offered to add 500 troops to Britain's 9,000-strong deployment, provided that other members of the 43-nation International Security Assistance Force also step up their contribution.

Yesterday he said that his conversations with the White House had left him assured that the UK strategy was "very much in line" with what US President Barack Obama wants to achieve in Afghanistan.

The ISAF coalition is currently awaiting a final decision from Mr Obama on whether to send tens of thousands more troops.

Mr Brown said that he had been contacting allies inside and outside Europe to ask them for their backing for the so-called "Afghan-isation" strategy of partnering and mentoring Afghan forces, so that they could eventually take over responsibility for security in their own country.

"We need our other Nato allies to help," the PM told BBC Radio 4's Today programme.

"I am asking them to help. I think we can probably get another 5,000 forces into Afghanistan from that Nato and outside Nato group and Britain will be part of that."

He added: "There has got to be burden-sharing amongst the alliance and I am sending people around Europe to persuade other countries that they should commit more troops.

"We are having some success. But as the debate over these last few months has shown, there is a lot more that we have to do.

"We are the only country actually to have said that we will provide more troops as things stand, but I believe that others will, including countries from Nato.

"Our strategy must be Afghan control of their own affairs. That will take some time, but then British troops can start coming home."

President Obama has held protracted consultations since receiving a report in September drawn up by General Stanley McChrystal, the commander of international forces in Afghanistan, calling for up to 40,000 more soldiers.

Expectations of an imminent decision were played down by the White House earlier this week, and dampened further when it was disclosed that US Ambassador in Afghanistan Karl Eikenberry had urged Obama to send no more troops until President Hamid Karzai had rooted out corruption.

Mr Brown was speaking after a leaked memo showed UK officials proposed a strategic reconciliation between the Afghan government and Taliban leaders.

The document, seen by the BBC, proposed removing "reconciled Talibs" from the UN sanctions list. It said the "right combination of carrot and stick, at the right moment, would be critical to changing the calculations of individual commanders and their men".

But Mr Brown said the key was to strengthen Afghan institutions so they could take control.

If Afghans who had been associated with the Taliban but were not ideologically extremist chose to renounce violence, there would be a possibility for reconciliation and reintegration. But he stressed: "It is not our strategy."

Moves to win over Taliban members were backed by the former chairman of the Commons Defence Committee, senior Labour backbencher Bruce George, who compared it to the compromises made to bring peace to Northern Ireland.

Mr George told a summit of the Nato Parliamentary Assembly in Edinburgh "There are attempts being made to negotiate, or to work with, some members of organisations at this point that are hostile.

"If this can help, then in my view this is to our advantage."

He added: "People said there would never be any engagement with Sinn Fein and the IRA – strange things happen in politics."


Germany to send 100 more troops

Germany will send more than 100 extra troops to Afghanistan in January, the country's defence minister announced today.

Karl-Theodor zu Guttenberg said the quick-reaction force soldiers would be deployed in the northern Afghan province of Kunduz, where there has been an increase in Taliban activity.

Most of the 4,365 troops Germany already has in Afghanistan are stationed there.

Thirty-six German soldiers have been killed so far and support in Germany for the war is low.

Mr Guttenberg announced the slight increase in troop numbers during a visit to his country's forces in Kunduz.