The former Ulster Unionist MP Sir Cecil Walker has died of a suspected heart attack at the age of 81.
Cecil Walker was MP for North Belfast for 18 years
Sir Cecil was the MP for North Belfast for 18 years, from 1983 until 2001, when he lost his seat to the DUP's Nigel Dodds.
He was awarded a knighthood in the Queen's Birthday Honours in June 2002.
Ulster Unionist leader Sir Reg Empey said Sir Cecil was "widely respected within the unionist family and will be sorely missed by all who knew him".
"Sir Cecil was a dedicated public servant who represented the people of North Belfast both as a councillor at Belfast City Council and for 18 years as MP for the area.
"His friendly and gentlemanly manner endeared him to both political friend and foe alike," Sir Reg said.
North Belfast UUP assembly member Fred Cobain said he had lunch with Sir Cecil last Thursday and the news of his death had come as a "dreadful shock".
"He was a tremendous individual and had a great rapport with ordinary working class people in the constituency," Mr Cobain said.
"This really has taken the wind out of those who knew him."
Mr Dodds, who won the North Belfast seat from Sir Cecil, said the "sudden and unexpected death has come as a terrible shock".
"Cecil Walker represented North Belfast through some of the darkest days of the troubles when the constituency bore the brunt of much of the violence.
"Through it all he always displayed great courtesy and acted with dignity in respect of political friend and opponent alike," Mr Dodds said.
SDLP North Belfast assembly member Alban Maginness expressed sympathy for Sir Cecil's family.
"Whilst we did not always agree politically I always found him gentlemanly and well intentioned.
"He certainly had a very firm commitment to peace and harmony in our community," Mr Maginness said.