Rev Ian Paisley, the former Northern Ireland First Minister had been admitted to hospital. Unconfirmed reports suggest he has suffered a heart attack. Paisley's wife Baroness Paisley confirmed her husband was being treated in hospital.
A family statement said: "She requests that the family's privacy be respected at this difficult time."
The founder of the Democratic Unionist party, and a former MP for Northern Ireland, he was rushed to Ulster Hospital, Dundonald, in Belfast on Sunday.
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The son of a dissident Baptist minister, Paisley was born in Armagh in 1926. He delivered his first sermon at the age of 16 and founded his own breakaway Free Presbyterian Church in 1951. A well known critic of the Catholic Church he once called the Pope “the Ant-Christ”.
In a historic move he became Northern Ireland’s First Minister in May 2007 after a deal was negotiated to share power with Sinn Fein.
The 85-year-old was the leader of the Democratic Unionist Party for almost 40 years. Last month he stood down from his role as a moderator of the Free Presbyterian Church. He delivered his final sermon at the Martyrs Memorial church in east Belfast just over a week ago.
See below for an Oxford Union speaker profile of Ian Paisley: