PESHAWAR (Pakistan) - PAKISTAN suspended truck shipments of US military supplies through the famed Khyber Pass after launching an offensive against militants who are trying to cripple Washington's war on a resurgent Taleban in neighbouring Afghanistan.

The US military said a temporary closure of the key supply line was not a problem, and praised the campaign in the rugged hills of northwestern Pakistan where al-Qaeda leaders - including Osama bin Laden - are believed hiding.

The operation on Tuesday came amid tensions between Pakistan and its eastern neighbour, India, triggered by last month's terror attack in Mumbai, which the Indian government and Washington have blamed on Islamic extremists based in Pakistan.

Pakistan urged India to pull back troops that it claimed had been sent near their border after Islamabad began moving troops toward the frontier. India said it had done nothing to aggravate tensions between the nuclear-armed neighbors. Both countries also appealed for calm.

Militants in the Khyber Pass have vowed to choke off supplies heading across Pakistan's western border to American and Nato troops in Afghanistan, where fighting is escalating seven years after the US-led invasion toppled a Taleban regime.

Western forces in landlocked Afghanistan rely on the winding, mountainous road for delivery of up to 75 per cent of their fuel, food and other goods, which arrive in Pakistan via the port city of Karachi. Ammunition and weapons are flown in.

With the US preparing to almost double the number of its soldiers in Afghanistan next year, the Western forces already were looking for alternate supply routes.

Last month, The Associated Press reported that Nato was close to reaching deals with Central Asian countries north of Afghanistan that would allow the alliance to truck in 'non-lethal' supplies from there.

Nato has reached a similar agreement with Russia that remains in force despite tensions triggered by the fighting in the former Soviet republic of Georgia this year, alliance officials said.

Mr Tariq Hayat Khan, the top administrator in the Khyber area, said Pakistani security forces were striking at militants using helicopter gunships and heavy artillery. Another official in the region said the road was closed because of the offensive.

'This operation will continue until the goal is achieved, which is nothing less then the elimination of trouble makers,' Mr Khan said. He said he had no information on any casualties.

Neither official said how long the road might be closed.

Suspected militants staged a series of raids on truck depots near the Pakistani city of Peshawar in recent weeks at the entrance to the pass, killing several guards and burning hundreds of vehicles.

In November, militants ambushed a supply convoy in the pass and seized several Humvees headed for US troops. They were pictured driving off in the vehicles, scoring a major propaganda victory.

'We are glad that they're helping clean out what they call miscreants in that area that have been attacking the supply line,' said Col Greg Julian, a US military spokesman in Afghanistan.

'Temporary closure (of the road) is not a problem. It's best that they conduct this operation and clear out these trouble spots.' American commanders insist the militant attacks on the supply line have not disrupted their mission in Afghanistan. They also say they have enough supplies to last many weeks in case shipping routes are blocked. -- AP