KABUL (AFP) - British Prime Minister David Cameron made an unannounced visit to Afghanistan on Saturday, backing talks with the Taliban as his top general said the West missed a chance to strike a peace deal 10 years ago.

Cameron visited troops in the southern province of Helmand before flying to Kabul for talks with President Hamid Karzai as the Afghan government and international powers try to revive stalled peace efforts.

"The encouraging thing, although there is a long way to go, is that the Taliban (have) said they no longer wanted Afghanistan to pose a threat to other countries," he said in Helmand in remarks reported by the BBC.

"There's a long way to go but alongside our security process, of a big and secure Afghan army and police force, a political process makes sense too." General Nick Carter told Saturday's Guardian newspaper that an opportunity to bring peace to Afghanistan was missed when the Taliban were on the defensive in 2002 after they were ousted following the 9/11 attacks.

"The Taliban were on the run," he said. "At that stage, if we had been very prescient, we might have spotted that a final political solution... would have involved getting all Afghans to sit at the table and talk about their future." Carter, deputy commander of the NATO-led coalition, acknowledged it was "easy to be wise with the benefit of hindsight" but Afghanistan's problems were political issues that "are only ever solved by people talking to each other".

The search for a peace settlement is now a pressing priority as the insurgency still rages across many parts of the country and 100,000 US-led troops prepare to exit next year.

A Taliban office in Qatar that opened on June 18 was meant to foster talks but instead triggered a diplomatic bust-up when the insurgents used the title of the "Islamic Emirate of Afghanistan" from their 1996-2001 reign.