Washington, Feb 2 (IANS): Amid credible reports that the Pakistan's spy agency ISI was secretly supporting Taliban insurgents to recover lost ground in Afghanistan, the United States has asked Islamabad to snap those ties and act against terrorist safe havens.

Secretary of State Hillary "raised many of these issues when she was in Pakistan last fall," State Department spokesperson Victoria Nuland told reporters Wednesday when asked about a leaked NATO report published in the British media about ISI's "manipulation" of Afghan Taliban's senior leadership.

"So from that perspective, obviously this is not new-our concerns about safe havens, our concerns about whether together we are doing enough to go after these groups, our interest in cooperating with the Pakistanis to do more," she said.

However, Nuland sought to play down the import of the report saying, "The context, as described by NATO, is that this is basically a summary of the views of those Taliban that we have in detention. So it's a summary of what they think, what they believe to be true."

The classified report shouldn't have come out into the open, she said suggesting, "It was not designed for any purpose other than to help those in the field understand what Taliban detainees were saying.

"So it was in no way designed to impact on our ongoing efforts to get back on track with Pakistan, which continue," Nuland said.

At the Pentagon, spokesperson Navy Capt John Kirby said US had "long standing concerns" about links between the elements of the ISI and the Taliban and wants Pakistan to "cut-off" those ties.

The facts brought out by the report were "not a new notion" and "the (Defence) Secretary (Leon Panetta) has been very clear about the ongoing problem of safe havens inside Pakistan for these groups," Kirby said.

"We have made it clear already that Pakistan needs to act against safe heavens. We would like ties between some elements of ISI and Taliban to be cut-off," he said.