Desmond Tutu, the Nobel Peace Prize-winning South African archbishop who was renowned for his opposition to the apartheid regime in his native country, refused to attend a summit with the former British Prime Minister, Tony Blair, due of Blair's decision to support the war in Iraq.

"Ultimately, the Archbishop is of the view that Mr. Blair's decision to support the United States' military invasion of Iraq, on the basis of unproven allegations of the existence in Iraq of weapons of mass destruction, was morally indefensible," Archbishop Tutu's office said in a statement.

The two men were supposed to attend the same leadership summit in Johannesburg later this week, but Tutu refused to be linked in any way with the man who put British forces into Iraq in 2003.

"The Discovery Invest Leadership Summit has leadership as its theme. Morality and leadership are indivisible. In this context, it would be inappropriate and untenable for the Archbishop to share a platform with Mr. Blair," the statement added.

Desmond Tutu, who a spokesman described as "a very prayerful man," "spent hours on his knees considering this decision," and simply can't allow himself to share the same platform with Blair.

Blair's office said in a statement the former Prime Minister was "sorry that the Archbishop has decided to pull out now from an event that has been fixed for months and where he and the Archbishop were never actually sharing a platform.

"As far as Iraq is concerned they have always disagreed about removing Saddam [Hussein] by force -- such disagreement is part of a healthy democracy.

"As for the morality of that decision we have recently had both the memorial of the Halabja massacre where thousands of people were murdered in one day by Saddam's use of chemical weapons; and that of the Iran-Iraq war where casualties numbered up to a million. including many killed by chemical weapons.

"So these decisions are never easy morally or politically".