Afghan president Hamid Karzai has suggested Western forces are withdrawing from Afghanistan because "they feel they were fighting in the wrong place" and that security in southern Helmand was better before Western troops arrived.
President Karzai said he thought that Helmand had been more peaceful before the arrival of US troops in 2006, and said he expects fighting in his country to diminish when foreign troops have gone as it will remove a grievance that drove many to take up arms.
He said: "The exit of foreign forces will not bring more violence for them to perpetrate against their own people, but a serious, strong, good reduction in violence will occur."
The Afghan leader told the Guardian and ITN that Western forces were not necessarily withdrawing because Afghanistan is now a safer place.
He questioned whether "they feel fulfilled with regard to the objective of fighting terrorism and weakening al Qaida, or they feel that they were fighting in the wrong place in the first place, so they should discontinue doing that and leave.
"There will not be peace in Afghanistan by having an agreement only between us and the Afghan Taliban.
"Peace will only come when the external elements involved in creating instability and fighting, or lawlessness in Afghanistan, are involved in talks."
He did not name the "external elements" which create instability in Afghanistan, but Karzai has long been a strident critic of the troubles in neighbouring Pakistan, with his government accusing Islamabad of "manipulating the insurgents".
His comments come ahead of the Prime Minister hosting in-depth discussions with President Karzai and Pakistan's president Asif Ali Zardari in an attempt to secure closer ties between Afghanistan and Pakistan.
President Karzai said he was more optimistic than a year ago that behind-the-scenes discussions between his government and the Taliban would prove fruitful, as relations with Pakistan improved.
And he praised Britain's position in negotiations, saying: "Britain's role at this point is highly valued in the pursuit it has for the peace process in Afghanistan and bringing Afghanistan and Pakistan together in a close dialogue."
While United Nations troops must withdraw from Afghanistan by the end of next year, President Karzai conceded that stability in the country would take longer as the Afghan police and army continue to struggle against the Taliban.
He admitted the government would not survive without western military and financial aid following the end of the Nato mission.
He told the Guardian that the seven-hour plane journey from Afghanistan counted as a welcome break, and said he had not taken any holiday in 12 years. "Of course I have felt the strain, of course one needs time off but it depends on whether one can afford it or not. I feel I cannot afford it, I feel I should continue to work for another year and then take a good leave and recuperate."
In the third round of discussions since last summer, the Prime Minister, President Karzai and Pakistan's Asif Ali Zardari will examine ways to promote regional stability as British troops prepare to leave Afghanistan by the end of next year.
The formal meeting follows a private dinner last night at the Prime Minister's official country residence.
Foreign Secretary William Hague, who attended yesterday's preliminary meetings, said the goal was to help the two nations "build closer co-operation around their common interest in a secure future".
Foreign ministers, Chiefs of Army Staff, Chiefs of Intelligence and the chairman of the Afghan High Peace Council will attend the talks for the first time.
The Prime Minister initiated the tri-lateral talks last summer at the request of both nations.