ISLAMABAD, Aug 24: Afghan President Hamid Karzai abruptly cancelled a speech to a state-run think tank in Pakistan on Tuesday, but officials denied security was a reason.

Mr Karzai, on the second day of a two-day visit to Islamabad, was due to speak at the city's Institute of Stategic Studies in the morning. He cancelled at the last minute citing "other engagements".

"President Hamid Karzai's talk at the Institute was called off at the request of Afghan government officials who have cited other engagements of the president as a reason for this request," said Pakistan's Foreign Ministry spokesman Masood Khan. "There was no security threat."

Mr Karzai had been due to speak before an invited audience at the institute, in what would have been the only semi-public appearance of his visit. His only other scheduled engagement before returning to Kabul is a meeting with Pakistan's outgoing Prime Minister Chaudhry Shujaat Hussain.

Security for Mr Karzai's trip has been extremely tight, given that he and Pakistan's President Pervez Musharraf, are prime targets for Osama bin Laden's Al Qaeda network and its militant allies. -Reuters