A Government minister has insisted there are no differences with the US over the timetable for withdrawing combat troops from Afghanistan.
Foreign Office minister Alistair Burt said it was only a "possibility" that withdrawal could begin from July 2011.
US President Barack Obama hopes to begin the withdrawal of US troops from the same date - but the head of the British military, General Sir David Richards,on Monday warned against a reduction in the UK's current force of 10,000 before 2012.
At Commons questions Pat Glass, Labour MP for North West Durham, said there had been "some differences in recent statements made by President Obama and Prime Minister David Cameron on troop withdrawal dates from Afghanistan".
She asked Mr Burt: "Can you confirm that President Obama and the Prime Minister are actually talking to each other on these important issues given that any discrepancies give succour to the Taliban and expose our troops to greater risk?"
The minister said: "I don't think there's any discrepancy. The interests of all the international forces, of which there are now some 48 countries represented, are the same: that is to ensure that Afghans have a stable, secure country which ensures that they have governance of themselves without outside influence.
"The work to ensure that that happens will be carried out by combat troops from this country until 2015 and the necessary work of development and governance will go on after that. The international forces are working together on these plans and proposals and are constantly in contact with each other and are working towards a series of political and military objectives in Afghanistan with the full co-operation and activity of the Afghan government."
Shadow Foreign Office minister John Spellar said: "In June the Prime Minister indicated that he was planning troop withdrawals from July 2011 and that is indeed reinforced in the business plan."
Mr Burt said: "I think the Prime Minister made it clear that was only a possibility and, of course, it depends on circumstances. The major commitment that's been made is to ensure that troop withdrawals are completed by 2015 and in that time ... the objective is to make sure that Afghans themselves have the opportunity to ensure that their country is secure through the Afghanisation of the police and through the Afghan national army."
Chief of the Defence Staff Gen Richards ruled out a reduction in Britain's current force of 10,000 before 2012 and claimed Britain would be "shouldering the burden" over the coming year.