Afghanistan risks 'failed state'

The study by former UN ambassador Thomas Pickering and retired Marine Corps General James Jones is due to be released later on Wednesday.

One of its recommendations is for more Nato troops to be sent to Afghanistan, the AP news agency reports.

The Taleban have mounted a comeback in Afghanistan over the past two years.

The south of the country has seen the worst violence since the Taleban were thrown out of power in the US-led invasion of 2001.

'Mounting challenge'

"Afghanistan stands at a crossroads," says the study which has been seen by AP.

"The progress achieved after six years of international engagement is under serious threat from resurgent violence, weakening international resolve, mounting regional challenges and a growing lack of confidence on the part of the Afghan people about the future direction of their country," it says.

The study also recommends the appointment of a US special envoy, and for Washington's Afghan policy to be decoupled from its Iraqi one.

Democrats in the US Congress have long argued that the Bush administration has failed to contain terrorism in Afghanistan by diverting resources to Iraq.

The Nato-led force has almost 37,000 troops in Afghanistan.