Former British foreign secretary Robin Cook, 59, who quit Prime Minister Tony Blair's cabinet in 2003 to protest the Iraq war, died Aug. 6 after collapsing on a Scottish mountain while walking with his wife.

Scotland's Northern Constabulary said Mr. Cook collapsed on Ben Stack in the Scottish Highlands. He was taken by coast guard helicopter to a hospital in Inverness, where he was pronounced dead.

Deputy Prime Minister John Prescott, filling in for a vacationing Blair, called Cook "the greatest parliamentarian of his generation."

Mr. Cook served as foreign minister from 1997 until 2001, when he was demoted to leader of the House of Commons. His resignation speech, days before the Iraq war began in March 2003, received a rare standing ovation from lawmakers.

"Why is it now so urgent that we should take military action to disarm a military capacity that has been there for 20 years, and which we helped to create?" he asked.

Renowned as an intelligent lawmaker and skilled debater, Mr. Cook remained a high-profile figure despite his withdrawal from government, and he became an increasingly vocal opponent of Blair's policies.

Some supporters believed that Mr. Cook should have been leader of the Labor Party. But Mr. Cook -- a short, bearded redhead -- declined to oppose Blair when he was elected Labor leader in 1994, declaring, "I am not good-looking enough."

Instead, he accepted the post of foreign secretary after Blair's 1997 landslide election victory.

But Mr. Cook's promise of an "ethical dimension" to British foreign policy often came back to haunt him, particularly after he sanctioned the sale of 16 Hawk jet fighters to Indonesia in 1999 despite the country's widely criticized human-rights record in East Timor.

Another diplomatic miscalculation came during a trip to India and Pakistan, when he suggested that Britain could mediate any negotiations over the disputed territory of Kashmir. The remark irritated both countries.

Mr. Cook was praised by many for his tough-minded handling of the 1999 Kosovo crisis, but that and other successes were partly overshadowed by the scandal of ending his 28-year marriage to his first wife, Margaret, at an airport as they were about to leave on vacation.

Warned by Downing Street that a tabloid newspaper was about to disclose his longtime affair with his secretary Gaynor Regan, Mr. Cook immediately told his wife that he was leaving her. She wrote a book accusing her former husband of being depressed and a drunk, saying that his intelligence and ability were unmatched but that he had "absolutely no natural courtesy or sympathy."

Mr. Cook later married Regan.

Mr. Cook was educated at Edinburgh University, where he studied English literature and began a career in Labor politics. He was first elected to parliament in 1974.

Survivors include his wife and two sons from his first marriage.

Robin Cook, left, with Yasser Arafat in 1998, was known as a skilled debater.