Mr Dewar's children arrive at the hospital

Mr Dewar's son Ian and daughter Marion, who arrived at Edinburgh's Western General Hospital on Wednesday morning, had been consulted by medical staff about their father's condition.

The 63-year-old politician had led the Labour/Lib Dem coalition government in Scotland since devolution May 1999.

He was admitted to hospital on Tuesday evening after falling outside his official Edinburgh residence, Bute House, in the morning.

Role of drug

Doctors discovered bleeding in his brain, which was complicated by him taking the blood-thinning drug Warfarin since major heart surgery in May.

His condition deteriorated and he was attached to a life support machine.

Medical staff at the hospital's news conference said the drugs contributed to Mr Dewar's death.

The role of the medication was complex and the condition was rare.

Donald Dewar: "Father of the nation"

Mr Whitton said: "His overall health was fine and in recent days his form was particularly good.

"He was starting to try and build periods into his day and week in which he could sit back instead of being in constant runs of meetings.

"It was the type of job, it had demands whatever your fitness or age."

'Great man lost'

After the fall, Mr Dewar accepted the advice to see someone and was taken to hospital.

"He was sat up in one of the trolley beds and he was fully aware of what was going on," Mr Whitton said.

"He had no idea of the brain haemorrhage, no-one had an idea."

His contribution to the historic process of devolution in recent years has been immense

Buckingham Palace

Mr Whitton ended the statement with the words: "Scotland has lost a great man."

Mr Dewar's ministerial colleagues in the Scottish Executive met informally on Wednesday morning to discuss the crisis.

Deputy First Minister Jim Wallace, a Lib Dem, has moved into the job, as he did when Mr Dewar underwent surgery.

Mr Dewar, who represented the Anniesland constituency in Glasgow, is credited with having played a pivotal role in bringing about Scottish devolution.

Meeting the Queen in Edinburgh

His tireless work earned him the title of "father of the nation" although he frequently played down his contribution in a typical self-deprecating manner.

Buckingham Palace said: "The Queen and all members of the Royal Family are shocked and deeply saddened by the news of Donald Dewar's death.

"His passion for Scotland and all things Scottish was renowned, and his contribution to the historic process of devolution in recent years has been immense.

"As her first minister in Scotland, Her Majesty has valued greatly his wise counsel and knows how much he will be missed in Scotland and wider afield."