Published Tuesday, 19 August 2014
First elected to Fermanagh District Council in 1981, Mr Foster served in the Assembly as an MLA for Fermanagh and South Tyrone from 1998 to 2002.
The 82-year-old had served in the B Specials and was a major in the Ulster Defence Regiment.
Mike Nesbitt said: "I was deeply sorry to learn of the passing of Sam Foster.
"Sam was a huge figure in Fermanagh unionism. It is a mark of Sam that he was able to gain the respect of political friend and foe alike.
"He never held personal grudges and sought to find agreement rather than create strife.
"He rose to high office but never forgot his roots and always remained at heart a Fermanagh man."
The UUP leader continued: "Sam was the living embodiment of a loyal Ulster unionist who served his country and his party faithfully for many decades and was held in the highest of esteem by all.
"I am proud to have known such a great unionist and Ulsterman and will be forever grateful for the generous support he gave when I joined the Ulster Unionist Party.
"My deepest condolences go out to his wife Dorothy and his family circle. He will indeed be sadly missed."
Mr Foster's nephew is married to DUP MLA and Enterprise Minister Arlene Foster.
He sparked controversy when he questioned how Arlene Foster could take on another job without neglecting her role as a mother.
On Tuesday, she hailed Sam Foster as an "important politician" for Northern Ireland.
"But for my husband, myself and my children he was foremost a very dear uncle," she said.
"It is well known that Sammy and I didn't always agree on the direction of unionism post the Belfast Agreement, but we did, especially in later years, realise the importance of family."
The DUP representative added: "I respected and admired Sammy's political style - his straight talking and ability to speak out on issues he felt strongly about.
"He will be missed across society, especially in the Loyal Orders, but most keenly by his beloved wife Dorothy, his daughter Helen, sons Mervyn and David and their respective families.
"I know, however, they will take great comfort from his deep faith and abiding trust in God."
Deputy First Minister Martin McGuinness also offered his condolences to Mr Foster.
"Despite our obvious political differences, I found him to be courteous, decent and conscientious at all times," said the Sinn Féin MLA.
Current Environment Minister Mark H Durkan praised the Ulster Unionist member's work in his department.
"He laid very good foundations which subsequent ministers have been able to build on," said the SDLP Assembly member.
Justice Minister and Alliance leader David Ford added: "Sam was somebody who was prepared to play his part in turning Northern Ireland around following the signing of the Good Friday Agreement.
"He will be warmly remembered."
UKIP MLA David McNarry described Mr Foster as a good friend.
He added: "Sam was a man of integrity, good nature and kindness. We are all the poorer for his passing."
© UTV News