Prime Minister Tony Blair (search) firmly denied Wednesday that the Bush administration signaled just months after Sept. 11 that a decision was made to invade Iraq, saying he was "astonished" by claims that leaked secret memos suggested the U.S. was rushing to war.

In an interview with The Associated Press a day after President Bush delivered a televised defense of the war in Iraq (search), Blair said defeating the insurgency was crucial to protecting security worldwide, and joined Bush in linking the war with the Sept. 11, 2001, attacks.

"What happened for me after Sept. 11 is that the balance of risk changed," said Blair, interviewed on the stone terrace overlooking the garden of his No. 10 Downing Street (search) offices, where policy meetings on Iraq were held before the invasion.

After Sept. 11, it was necessary to "draw a line in the sand here, and the country to do it with was Iraq because they were in breach of U.N. resolutions going back over many years," he said. "I took the view that if these people ever got hold of nuclear, chemical or biological capability, they would probably use it."

Blair was asked about the leaked memos, which suggest strong concerns in the British government that the Bush administration was determined in 2002 to invade Iraq — months before the United States and Britain unsuccessfully sought U.N. Security Council (search) approval for military action.

"People say the decision was already taken. The decision was not already taken." Blair said he was "a bit astonished" at the intensive U.S. media coverage about the memos, which included minutes of a July 23, 2002, meeting between Blair and top officials at his Downing Street office.

According to the minutes of the meeting, Sir Richard Dearlove, then chief of Britain's intelligence service, said the White House viewed military action against Saddam Hussein as inevitable following the Sept. 11 attacks. Bush "wanted to remove Saddam, through military action, justified by the conjunction of terrorism and WMD" (weapons of mass destruction), read the memo, seen by the AP. "But the intelligence and facts were being fixed around the policy."

In the interview, Blair said raising such concerns was a natural part of any examination of the cause for war.

"The trouble with having a political discussion on the basis of things that are leaked is that they are always taken right out of context. Everything else is omitted from the discussion and you end up focusing on a specific document," he said. "It would be absolutely weird if, when the Iraq issue was on the agenda, you were not constantly raising issues, trying to work them out, get them in the right place," he said.

Blair suggested that ensuring victory in Iraq was now more important than debating the case for invasion.

"The most important thing we can do in Iraq is concentrate on the fact ... that what is happening there is a monumental battle that affects our own security," he said. "You've got every bad element in the whole of the Middle East in Iraq trying to stop that country (from getting) on its feet and (becoming) a democracy."

Blair echoed Bush's pledge a day earlier to keep U.S. forces in Iraq until the fight is won. "There is only one side to be on now and it is time we got on it and stuck in there and get the job done, and not leave until the job is done," he said.

Blair won a historic third term in office last month. But his Labour Party saw its parliament majority slashed, largely because of discontent over Iraq. While Blair's close ties to Bush have cost him with voters at home, he said it's that relationship which allows the countries to talk about tough issues.

"My support for America is not based on you give us support for this and you get that in return," Blair said. "I should only do what is right for Britain. The president should only do what is right for America, and we should both try to do what is right for the world."

That alluded to Blair's ambitious twin goals for next week's summit in Scotland of the world's eight most industrialized nations — reaching consensus on fighting climate change, and greatly boosting aid to Africa. On climate change in particular, Blair said the going may be rough.

"On climate change there obviously has been a disagreement over Kyoto," Blair said referring to the Kyoto Protocol, which the Bush administration has rejected. He said he hoped to reach agreement on moving toward a low-carbon economy that curbs greenhouse gas emissions.

"On Africa, I don't think there is a disagreement about the basic principles of what we are trying to achieve and obviously I hope that by the time we get to the summit next week we have got agreement on the substance of the package."

Blair is calling for fair trade in Africa and an extra $25 billion a year in international aid for the continent by 2010, and a further $25 billion annually up to 2015.

Blair, looking tanned and relaxed, has said he won't run for another term, and on Wednesday he brushed aside a question about what he might do after leaving office.

"I don't spend a lot of time thinking about it because the job is pretty all-engrossing. If you believe in what you are doing, it is exciting to take on the challenge and try to do it."

Next to the terrace was the Cabinet room, where the walls are lined with tomes on the lives of Benjamin Disraeli and other predecessors. Does he remain as full of energy as in 1997, that heady time of promise when he first joined their ranks?

"Yes, I do," he replied. "In fact, I feel vigorous and enthusiastic."