Irish politician and Nobel Peace Prize winner John Hume died aged 83, Sky News TV channel reported referring to his family.
"John Hume was a political titan; a visionary who refused to believe the future had to be the same as the past," former Prime Minister Tony Blair said.
"His contribution to peace in Northern Ireland was epic and he will rightly be remembered for it.
"He was insistent it was possible, tireless in pursuit of it and endlessly creative in seeking ways of making it happen."
John Hume was born in 1937 in Londonderry, Northern Ireland, to a Catholic family. In 1970 he was among the founders of the Social Democratic and Labor Party, from 1979 to 2000 he was its leader.
In 1979 he was elected Member of the European Parliament, in 1983-2005 he was a member of the House of Commons of the UK Parliament, and in 1998-2000 - of the Northern Ireland Assembly.