British Prime Minister Tony Blair was expected to allay concerns if Musharraf brought the matter up at talks outside London, officials said Thursday, underlining that the report in question is not official.

Speaking before heading for the talks, Musharraf denied allegations that Islamabad's ISI indirectly supports extremism in Afghanistan, Iraq and Britain by backing Pakistan's Islamist parties.

"Absolutely, 200 percent, I reject it," Musharraf told the British Broadcasting Corp. "I take exception seriously, and I would like to talk about it (with) Prime Minister Tony Blair when I meet him."

The two leaders were set to meet in the evening at Blair's countryside retreat of Chequers to discuss mainly the common fight against terrorism as well as the situation in Afghanistan.

"In both of those areas, we have a very constructive relationship with Pakistan," said a spokesman in Blair's Downing Street office.

If Musharraf raises his complaint, the spokesman added, "the prime minister will be able to give him assurances" the report "is not an official document, has no official status, and doesn't represent the views of the government."

His remarks echoed those of the Ministry of Defence.

The BBC cited a leaked paper written by a senior military official linked to Britain's foreign intelligence service MI6 who served on a fact-finding mission to Pakistan in June which interviewed army officers and academics.

The paper written for the Defence Academy, a Ministry of Defence (MoD) think tank, alleges that the ISI is fanning extremism by secretly backing the coalition of religious parties in Pakistan known as the MNA.

"The army's dual role in combating terrorism and at the same time promoting the MNA, and so indirectly supporting the Taliban through the ISI, is coming under closer and closer international scrutiny," the paper said.

A spokesman in Blair's office said the two leaders will focus on two things. our partnership together on fighting terrorism and on the situation on Afghanistan. In both of those areas, we have very sort of constructive relationship with Pakistan

With Pakistan's support, the United States and its allies toppled Afghanistan's Taliban rulers in 2001 for harboring the Al-Qaeda group that staged the September 11 attacks.

However, the Taliban is making a comeback in Afghanistan five years later.

And the report by the Defence Academy said Britain's support for Musharraf is flawed because Pakistan is "on the edge of chaos" rather than being a pillar of stability.

"Indirectly Pakistan, through the ISI, has been supporting terrorism and extremism whether in London on 7/7 or in Afghanistan or Iraq," it said.

At least two of the four suicide bombers who blew themselves up in London last year, killing themseles and 52 other people, had visited Pakistan where they are suspected to have contacted extremist groups.

The report proposed using the military links between the British and Pakistan armies at a senior level to persuade Musharraf to step down, accept free elections and persuade the army to dismantle the ISI.

Musharraf, who seized power in a 1999 military coup, responded angrily to the suggestions, saying: "I would like to tell this Ministry of Defence spokesman to say the Ministry of Defence maybe should be dismantled before the ISI is dismantled."

He said the ISI was a "disciplined force" which "won the Cold War for the world."

Musharraf was in Washington along with Afghanistan's President Ahmed Karzai for talks with US President George W. Bush.