US-Pakistan co-operation strengthens

By Nick Childs BBC Pentagon correspondent

A week ago, there was a flurry of speculation that the Pakistani armed forces may have cornered a top al-Qaeda member, perhaps even the number two, Ayman al-Zawahri.

So far, that has come to nothing.

But there is no doubt that both the US and Pakistan are continuing their efforts to squeeze the remnants of al-Qaeda and the Taleban in the key border area which separates Afghanistan and Pakistan.

Co-operation between the US and Pakistani militaries on this front has never been closer.

Pentagon officials insist that operations on the Pakistani side of the border are a matter for the Pakistanis.

Improving surveillance

But the strategy is very much a joint one, in effect a pincer movement or, as one senior US commander has described it, a "hammer and anvil" approach.

Washington is aware US troop presence in the border region is an issue

The Americans would, of course, be happy to provide whatever military help Pakistan could live with.

But Washington is aware of how sensitive this is for the Pakistani authorities.

US officials insist that no US combat forces are directly involved with the Pakistanis.

But support is another matter. US officials suggest that the US has helped with some specialist training and even some high-tech surveillance equipment, such as ground sensors that can monitor vehicle movements.

The US has also stepped its own surveillance efforts, as part of its own operations.

These include greater use of unmanned drones and sophisticated aircraft such as the Rivet Joint - which can monitor communications and other electronic activity - and the Joint Stars, which uses radar to monitor ground movements.

The Pentagon is very cagey about how these are used.

But, as one US official put it, you can be sure surveillance information is provided to the Pakistanis when it is relevant to their operations in the border area.

Human intelligence

Of course, high-tech surveillance is all very well and has its uses.

Pentagon officials acknowledge that, in many ways, the key difference between this and previous offensives against the al-Qaeda and the Taleban is the more active role of the Pakistani military in its sensitive tribal areas

It can, for example, help narrow a search area. But many US officials acknowledge that, in the end, what probably counts most is good human intelligence on the ground.

That, after all, is what caught the former Iraqi leader, Saddam Hussein.

And the mountainous and difficult nature of the terrain in the border areas between Afghanistan and Pakistan can limit the effectiveness of some high-tech intelligence gathering.

For its part, the US military is clearly ready to pounce on any al-Qaeda or Taleban fleeing the Pakistani operations.

The Americans themselves are engaged in Operation Mountain Storm.

US officials says it is still in its early phases.

But it could ultimately involve thousands of US and Afghan forces, trying to increase the military pressure in the Afghan border areas.

Extra firepower

There are some 12,000 US forces in Afghanistan and they are about to be joined by up to 2,000 or so extra US marines.

US officials suggest this bolstering of the force has as much to do with trying to maintain stability in the run-up to critical elections in Afghanistan as it is connected to any offensive.

But these new marines could bring considerable extra firepower and have special operations training.

Still, Pentagon officials acknowledge that, in many ways, the key difference between this and previous offensives against the al-Qaeda and the Taleban is the more active role of the Pakistani military in its sensitive tribal areas.

However it is causing controversy for the Pakistani government at home.