The Prime Minister said there should be two "fairly even withdrawal steps" of troops from Afghanistan between now and the end of 2014.
The Prime Minister said there would be 5,200 troops remaining in Afghanistan by the end of 2013. Post 2014, the Mr Cameron said "we have not made any exact decisions yet" but said his focus was on ensuring a stable future for the country.
Earlier today Mr Cameron spoke to Afghan President Karzai on the phone. He told MPs in the House of Commons:
After December 2014, we will not be leaving Afghanistan, we have pledged to help the people of Afghanistan. The thing we are most focused on is bringing Pakistan and Agfhanistan together to discuss their future, and I spoke to President Karzai earlier today.
A Conservative backbencher has said that the government's decision to withdraw troops from Afghanistan will be "difficult and dangerous".
ITV News understands that Britain's withdrawal from Afghanistan may be speeded up with troop numbers almost halved in the next year.