Politicians of all parties have been paying tribute to Lord Williams of Mostyn, leader of the House of Lords, who has died at the age of 62.
Tributes have flooded in for a witty and clever man
Welsh-born Lord Williams collapsed and died suddenly at his home in Gloucestershire on Saturday.
His family are still not sure what caused his death, Lord Williams' private secretary, Chris Jacobs, told reporters.
The peer's colleagues have been praising him for his outstanding intelligence, warmth and wit.
A "profoundly shocked and saddened" prime minister described his cabinet colleague as a "fine politician with excellent judgment".
Tony Blair said in a statement that his friend had been a "kind and generous man" who "sparked huge affection in all those who knew him".
"A superb and entertaining
speaker, he used his wit and general humour time and time again to diffuse difficult situations in the Lords," Mr Blair said.
"He was a politician at the height of his powers who played as always a full
role in cabinet discussions on Thursday.
"It will be hard for his cabinet colleagues and his many friends within and outside politics to accept that we will not see him again."
Lord Williams was a former lawyer who was steering the process of reform of the upper chamber of Parliament.
Analysts said he was so popular, it was hoped he could bring about the modernisation of the Lords by consensus.
Ironically, only last week the government all but abandoned efforts to find that consensus, announcing plans to axe the remaining 92 hereditary peers from the Lords.
Lord Newby - for the Liberal Democrats - said Lord Williams had been a "delightful wit", who was greatly respected and a master of his brief.
The Tory shadow leader of the Lords, Lord Strathclyde, said the news of his death had cast a "long shadow" over the House.
"He performed his duty with a mixture of dry wit and an acute political edge... we have lost a fine political figure," he said.
Lord Williams had also been a passionate campaigner for a children's commissioner, the appointment of which was recently announced by the government.
Mary Marsh, chief executive of the children's charity NSPCC, said his death was an enormous loss.
"Children have lost a wise and great champion for children," she said.
Lord Williams was appointed Leader of the Lords in June 2001, having been Attorney General and Deputy Leader of the Lords since 1998.
At one point a deputy High Court judge, Lord Williams was chairman of the Bar Council in the early 1990s and was made a life peer in 1992.
A Welsh-speaking lawyer, he first held political office in 1992 when he became Opposition spokesman on legal affairs.
He believed strongly in reform of the legal profession, and had argued for the separation of elected officials and the law, and particularly the setting up of a supreme court and legal appointments commission.
The two reforms were among changes to the judiciary announced by the government earlier this year.
Deeply involved in academia, he held honorary posts at the University College of Wales in Aberystwyth, the University College of North Wales and was pro-Chancellor at the University of Wales and president of the Welsh College of Music and Drama.
Lord Williams, who was born Gareth Williams near Prestatyn, north Wales, in 1941, was married and leaves three daughters and one son.