David Cameron has confirmed there will be "opportunities" in all countries for early troop withdrawal from Afghanistan.
But, in an apparent swipe at French President Nicolas Sarkozy - who announced early French troop withdrawal - he said the decision should be based on Afghan progress in all Nato states.
Speaking on Saturday after bilateral talks at Chequers with Afghan President Hamid Karzai, the Prime Minister reaffirmed his desire for there not to be a "cliff edge" in 2014, when combat forces are due to exit.
Cameron said: "Obviously, between now and 2014 there will be opportunities for different countries to reduce their troop numbers.
"Britain has reduced our troop numbers over the last year."
The prime minister's announcement follows Sarkozy's declaration France would withdraw its combat troops from Afghanistan a year early, prompting accusations of Sarkozy putting domestic politics ahead of Afghans' safety, the Associated Press reported.
But Cameron continued to say:
"I don't want to see some sort of cliff edge in 2014 when all of the remaining troops come out at once but clearly, between now and 2014, the rate at which we can reduce our troops will depend on the transition to Afghan control in the different parts of Afghanistan and that should be the same for all of the members of Nato who are all contributing and helping to a strong, stable and peaceful Afghanistan, which is in all our interests."
Cameron added Britain "has paid a heavy price" for fighting insurgency but insisted progress was being made.
He paid tribute to the latest British casualty in Afghanistan, a soldier from the 1st Battalion The Yorkshire Regiment, and said his thoughts were with the man's family.
A total of 397 British forces personnel or MoD civilians have died while serving in Afghanistan since the start of operations in October 2001.
Cameron and President Karzai signed a pledge setting out the next stage in relations between Britain and Afghanistan.
The "enduring strategic partnership" renews a 2005 agreement and sets out a shared vision of a secure, stable and prosperous Afghanistan able to maintain its own security and prevent the country from being used as a safe haven for international terrorists.
Cameron said the level of violence was down across the country, particularly in Helmand, and the building of the national army and police force were "on target".
During a working lunch the pair discussed security progress as well as the future support needed from the international community post 2014.
Cameron said the long term relationship would focus on diplomacy, aid, trade and investment.
"I think part of achieving that is not just what we are doing on the ground with all the Nato partners but also the need for what the President and I have often spoken about, for a political process that ensures all Afghans, if they give up violence, if they give up terror, can play a part in a strong democratic state for the future."
President Karzai said Britain had been Afghanistan's "steadfast friend" over the last decade.
The Afghan people "appreciate" the "sacrifices" that have been made, he added.
"May I convey to the people of Britain the gratitude of the Afghan people for all that Britain has offered Afghanistan, for having been ready to sacrifice, and having been ready to share, hard earned taxpayers' money with Afghanistan for the benefit of the Afghan life."