Washington, March 12 (IANS) Leading South Asia experts say the US should be prepared to take action against the Lashkar-e-Taiba (LeT), blamed for the Mumbai terror attacks, if Pakistan is unable or unwilling to act against the terror outfit that remains its spearhead against India.

'Doing so may be increasingly necessary not simply to prevent a future Indo-Pakistani crisis, but more importantly to protect the United States, its citizens, its interests, and its allies,' Ashley Tellis of the Carnegie Endowment for International Peace told a Congressional panel Thursday.

With the exception of Al Qaeda, LeT is arguably the most important terrorist group operating from South Asia and was the mastermind of the November 2008 Mumbai attacks, he said at a hearing of the House of Representatives subcommittee on the Middle East and South Asia on the LeT threat.

Suggesting that LeT 'remains the spearhead of the Pakistani military's campaign against India', Tellis said: 'LeT remains primarily Pakistani in its composition, uses Pakistani territory as its main base of operation, and continues to be supported extensively by the Pakistani state, especially the army and Inter-Services Intelligence (ISI).'

LeT's ambitions extend beyond India, Tellis said, suggesting the US should stop pretending that LeT is an independent actor. 'A candid recognition that the organisation receives protection and support from the Pakistani state would go a long way toward solving the problem.'

Noting that since the attack on Mumbai, India and the US have successfully partnered together on matters of intelligence and counter-terrorism, he said: 'This cooperation should expand further.'

Pakistani expert Shuja Nawaz, director, South Asia Centre at the Atlantic Council of the US, said the LeT represents 'a Frankenstein's monster' that appears to have taken on a broader regional role.

'Another Mumbai-type attack involving the LeT might bring India and Pakistan into conflict, a prospect that should keep us awake at night,' he said.

In Pakistan, both the civil and the military now appear to recognise the existential threat from home grown militancy, Nawaz said noting: 'The army appears to have dislocated the Tehreek-e-Taliban of Pakistan. Yet, it faces a huge and, to my mind, greater threat in the hinterland, in the form of the LeT.'

Pakistan expert Lisa Curtis said Washington must develop policies that approach the LeT with the same urgency as that which the US deals with the threat from Al Qaeda.

'Given the potential for LeT-linked terrorist cells to conduct a Mumbai-style attack here in the US, Washington must pursue policies that contain and shut down the operations of this deadly organization,' she said.

This will require close cooperation with the Pakistani government, which has in the past supported the LeT, and only recently and haltingly begun to take steps to rein in the group's activities, said Curtis, a senior research fellow at the Heritage Foundation.

The arrest of Pakistani American David Coleman Headley, accused of scouting targets for the Mumbai terrorist attacks, showed the Pakistani military's apparent closeness to LeT, she said while noting a former army officer was named as Headley's handler.

Marvin Weinbaum, a professor and scholar-in-residence at the Middle East Institute, said the LeT could surpass or replace Al Qaeda as the number one terror network worldwide.

The Paksitan-based outfit threatens American and Western interests, and not just India as originally conceived by its sponsor, the ISI, he said. LeT 'has evolved from being a government-sponsored Pakistani jihadi group dedicated to an insurgency in Indian Kashmir into a terrorist organization with regional and global ambitions and reach'.