Cameron during his meeting with British forces in Camp Bastion in Helmand province said that the troops can come home from Afghanistan knowing it was mission accomplished.
He praised the role of the British forces in Afghanistan and said that a basic level of security had been achieved.
In the meantime, Cameron vowed that Britain will not abandon Afghanistan and will continue to support the Afghan national security forces.
Cameron said that the combat role of the British forces will end by the end of 2014.
United Kingdon has deployed around 5,200 troops under the NATO-led International Security Assistance Force (ISAF) mission in Afghanistan.
Majority of the British forces are based in southern Helmand province of Afghanistan. At least 446 British troops have been killed in various incidents since the beginning of its mission in Afghanistan.