Amid increasing pressure by the United States to rein in the Inter Services Intelligence for its involvement in terrorist activities, including the Indian embassy blast in Kabul, Pakistan has said it would investigate the matter if evidence were presented to it against any of its nationals.

"If any evidence were to be presented against any individual in Pakistan, or against the interest of Pakistan's neighbours, then the government would certainly act on that evidence," Pakistan's Ambassador to the US, Husain Haqqani, was quoted as saying by The New York Times on Saturday.

Haqqani, however, laid the blame for 'several outstanding problems' in the Pak-US ties on President Pervez Musharraf [Images] who was firmly in power until elections earlier this year.

"Several outstanding problems in the relationship between the United States and Pakistan that the elected government inherited from the past are currently being resolved," Haqqani said. "These include issues of trust between our two intelligence services," he was quoted as saying.

During meetings in Washington this week with Pakistan premier Yousuf Raza Gilani, senior Bush administration officials pressed Islamabad [Images] to assert control over ISI, the NYT quoted American officials as saying.

The American pressure also reflects heightened concerns at the State Department, Pentagon and Central Intelligence Agency that operatives in the ISI, who have long been believed to have close ties to Pakistani militants, have become bolder and more open in their support for militant organisations.

The NYT reported that American intelligence agencies had said they have evidence that members of the ISI helped plan the deadly July 7 suicide bombing of India's embassy in Kabul, which left nearly 60 people, including four Indians, dead.

The paper quoted a Bush administration official as saying that Pakistan's government had yet to assure the administration that it could control the ISI. "There are real questions about the organisation's loyalty," the official said.

"In the wake of political gridlock and a lack of a clear political direction, some elements of the ISI have started to exercise certain prerogatives," he added.

But the paper quoted some experts as saying that the Bush administration should be more patient in allowing the new Pakistani government to assert its authority after years of military rule in Pakistan.