Former Labour Prime Minister James Callaghan, who presided over a chaotic winter of strikes that opened the door to Margaret Thatcher's radical free market reforms, died yesterday on the eve of his 93rd birthday.

His family said Callaghan, known as "Sunny Jim" for his avuncular character, died at his home in southern England just 11 days after the death of Audrey, his wife of 67 years.

"Jim Callaghan was one of the giants of the Labour movement, whose long and active life almost spans the history of the party he served so superbly," Tony Blair, Britain's first Labour Party prime minister since Callaghan said. "In later times I sought his counsel many times and found his judgement and common sense invariably sound."

Political opponents as well as friends paid tribute to Callaghan. Former Conservative Prime Minister Edward Heath, Thatcher and current Conservative leader Michael Howard all praised him for his decency and kindness.

Queen Elizabeth sent a message of condolence to Callaghan's family and Prince Charles described him as "a remarkable man".

Callaghan, from a modest working-class background and, unusually for a British prime minister, lacking any university education, became prime minister in 1976 after the surprise resignation of Labour leader Harold Wilson.

But he lasted just three years before the strong ties he had nurtured with the trade union movement all his life unravelled chaotically through the bitter winter of 1978-9, when a battery of pay strikes plunged the country into misery. Some said it was misjudgment in timing that lost him the election of May 1979 to the Conservative Party.

The defeat paved the way for Thatcher's free-market revolution and 18 years of Conservative government.

Callaghan was the only man to have held all four top offices of state - prime minister, foreign secretary, home secretary and chancellor of the exchequer.