Singh, wrapping up a four-day visit to the United States, said the al-Qaeda terror network led by Osama bin Laden had a key base in Pakistan and that there was always the risk of Islamic militants seizing power in Pakistan.

In an interview with the CNN broadcasting network, the 72-year-old Indian leader said that he was worried about the security of Pakistan's nuclear assets should President Pervez Musharraf be replaced.

"Well, the security of (nuclear) assets which are under control of Pakistan, I think does worry us. And I hope that credible solutions can be found today with that problem," Singh said.

Asked what specifically worried him about the nuclear weapons, he said, "Well, if they get into the hands of the Jihadi element, that could pose a serious problem."

"I hope that this does not happen. And I pray that it will not happen."

On whether he was concerned that Islamic extremists in Pakistan could take charge, Singh said: "Well, there is always a danger.

"And we would like Pakistan to emerge as a moderate Islamic state, and we have a vested interest in the stability and progress in Pakistan."

Singh was also asked whether bin Laden and al-Qaeda still had a "significant base" in Pakistan. "Well, I think there's no doubt about this," he said.

Both India and Pakistan conducted tit-for-tat nuclear tests in 1998. They fought three wars since their independence in 1947 from Britain, two of them over the Himalayan state of Kashmir, which is divided between them and claimed by both in full.