Washington: The US today acknowledged that its ally Pakistan keeps ties with anti-India terror group Lashkar-e-Taiba, but said Washington had "no choice" but to maintain its relations with Islamabad if it has to fight Al Qaeda in the region.

In possibly the first such hard-hitting statement on Pakistani establishment's links with terror networks by the top Pentagon official, Defense Secretary Leon Panetta said the US is concerned by this and such issues make ties with Islamabad "complicated".

"We're concerned with... the relationships that Pakistan has, what makes this complicated, is that they have relationships with the Haqqanis, and the Haqqani tribe are going across the border and attacking our forces in Afghanistan, and it's pretty clear that there's a relationship there," he said.

He further went on to acknowledge that Pakistan continues to have ties with the LeT which has targeted India on more than one occasion.

"There's a relationship with LeT. And, you know, this is a group that goes into India and threatens attacks there, it has conducted attacks there," Panetta said in response to a question at National Defense University.

India has long blamed Pakistan for supporting anti-India terror groups, including the LeT which orchestrated the 2008 Mumbai attacks, despite being a close US ally in the 'war on terror'.

However, Panetta and Secretary of State Hillary Clinton, argued in a joint public appearance that it was not possible to cut off relationship with Pakistan as the nuclear-armed country provided some crucial cooperation in fighting Al Qaeda in Afghanistan.

Tags: Lashkar e Taiba, Pak and Laskhar, Pak Lashkar ties, Pakistan and LeT, US and Pakistan