LONDON: The Pakistani security services are secretly helping Afghanistan's Taliban, who assume their victory is inevitable once Western troops leave, a secret Nato document says, according to reports on Wednesday.

The leaked “State of the Taliban” report – seen by the BBC and The Times newspaper – was compiled from information gleaned from insurgent detainees and was given to Nato commanders in Afghanistan last month, the media reports said.

It claims that Pakistan and its ISI intelligence agency are aware of the locations of senior Taliban leaders.

The BBC said the report was based on material from 27,000 interrogations of more than 4,000 captured Taliban and Al-Qaeda operatives, plus other foreign fighters and civilians.

“Pakistan's manipulation of the Taliban senior leadership continues unabatedly,” the report was quoted as saying.

“ISI officers tout the need for continued jihad and expulsion of foreign invaders from Afghanistan.”

The Times quoted the report as saying the Taliban's “strength, motivation, funding and tactical proficiency remains intact”, despite setbacks in 2011.

“Many Afghans are already bracing themselves for an eventual return of the Taliban,” it said.

“Once (Nato force) Isaf is no longer a factor, Taliban consider their victory inevitable.”

Kabul, which accuses Islamabad of supporting the 10-year Taliban insurgency in Afghanistan, put relations on ice after the September murder of its peace envoy Burhanuddin Rabbani, which one Afghan minister blamed on Pakistani spies.

The US Department of Defense said it could not comment on the report but set out its fears about Pakistan and its influence in Afghanistan.

“We have not seen the report, and therefore cannot offer comment on it specifically,” Pentagon spokesman George Little told AFP.

“We have long been concerned about ties between elements of the ISI and some extremist networks.” US Defense Secretary Leon Panetta said.

In its conclusion, the report said there had been unprecedented interest in joining the Taliban cause in 2011 – even from members of the Afghan government.

“Afghan civilians frequently prefer Taliban governance over the Afghan government, usually as a result of government corruption,” it was reported as saying.

The Times, in an editorial, said Pakistan was “actively hindering reconciliation” between the Taliban and Kabul.

“Islamabad appears to be engaged in a systematic effort to destabilise the Kabul government of (President) Hamid Karzai prior to the withdrawal of Western forces, and to assist those attacking and killing those forces.”

“The ISI emerges from this document looking considerably more villainous, even, than the Taliban itself.”

“The picture that is painted is very much one of a force that both expects, and is widely expected, to have a big stake in controlling the Afghanistan of the future.”