LONDON (Reuters) - Former Foreign Secretary Robin Cook, who quit government over the Iraq war, died on Saturday after collapsing on a Scottish mountainside. He was 59.
Prime Minister Tony Blair warmly praised Cook as an intellectual and political heavyweight despite their clash over the decision to back the United States in Iraq in 2003.
"This news will be received with immense sadness, not just in Britain but in many parts of the world," Blair said.
"Robin was an outstanding, extraordinary talent -- brilliant, incisive in debate, of incredible skill and persuasive power."
Cook served as foreign secretary from 1997 to 2001 and then became Leader of the House of Commons -- the government's top representative in parliament. He served in that post until 2003.
Cook collapsed on Saturday while walking with his wife Gaynor on Ben Stack mountain in northwest Scotland, police said.
A rescue helicopter took him to hospital in the town of Inverness, where he was pronounced dead.
Colleagues praised Cook as one of the outstanding political debaters of his era. He drew widespread praise for an eloquent resignation speech when he quit the government.
"Though we disagreed over Iraq, I always respected the way in which he put his case," Blair said.
Cook, a Scot, took over the Foreign Office after a landslide election win by the Labour party, pledging a new "ethical dimension" to foreign policy.
But his first year in office was marked by personal embarrassment and questions over his judgement.
He abruptly ended his 28-year marriage to first wife Margaret when a newspaper threatened to reveal he was having an affair with his secretary Gaynor Regan, whom he later married.
KOSOVO CAMPAIGN
He survived the scandal to play a prominent role in NATO's 1999 campaign to force Serbian troops out of Kosovo. He later listed "defending Kosovo" as one of his greatest achievements.
Muslim leaders praised Cook's opposition to the Iraq war. Human rights activists lauded his commitment to international justice and control of the arms trade.
"He helped expose the need for more stringent controls on an arms trade that all too often leads to weapons ending up in the hands of tyrants and human rights abusers," said Mike Blakemore, media director of Amnesty International.
Although his switch to become leader of the House of Commons was a demotion, Cook took on the task with vigour and sought to modernise centuries-old traditions in parliament.
He also seemed to relish life on the backbenches after quitting the cabinet. He published a highly acclaimed book on his years in government and wrote frequent newspaper columns.
"I admired and valued Robin as a colleague and friend and as one of the greatest parliamentarians of our time," said Chancellor of the Exchequer (finance minister) Gordon Brown.
Commentators had speculated that Brown, who is widely expected to succeed Blair in the coming years, would recall Cook to the government.
In his free time, Cook was fanatical about horse racing and wrote newspaper articles about the sport.
When asked which book he would take with him if he were banished to a desert island, he chose the National Hunt Form Book, a guide to horse racing in Britain.
The son of a chemistry teacher, he was studied English at Edinburgh University, where he began a career in Labour politics. He was first elected to parliament in 1974.