The Afghan president, Hamid Karzai, has told the Today programme that his country may need foreign support for another 15 years to keep the Taliban out of power.

Interviewed in Number 10 Downing Street by presenter James Naughtie, President Karzai - who is in London for a major conference on Afghanistan's future - said that his country would rely on international help for some time to come.

"With regard to training and equipping the Afghan security forces, 5 to 10 years will be enough," he explained. "With regard to sustaining them until Afghanistan is financially able to provide for our forces, the time may be extended to 10 to 15 years."

And Gordon Brown, who was interviewed alongside the president, said that the Afghan Taliban represented a wide range of divergent views. "Some are ideologically committed and support Al Qaeda," he said.

"But some are mercenaries, some are people who are local nationalists, some have got local tribal grievances.

"We can divide them, and it's important that we do so, but there is no reconciliation with the Al Qaeda element who believe that violent extremism and the murder of people is an expression of a perverted view of Islam."