Former European Commissioner, Senator and Fianna Fáil Minister Michael O'Kennedy, a native of Co Tipperary, has died aged 86.
President Michael D Higgins said his former parliamentary colleague "served the Irish people at home and abroad in a number of capacities and always with distinction".
He said people "throughout Tipperary and beyond will have been saddened to hear today of his death".
The President added that Mr O'Kennedy "gave his life to public service across such a wide range of roles".
Taoiseach Micheál Martin said he was "deeply saddened" by his passing and that "few people have left such a rich, or long, political legacy, or dedicated so much to Irish public life".
He recalled: "Fighting his first election in 1965, Michael served the people of Tipperary North with great commitment as a TD from 1969, and many times more until 2002.
"A man of great integrity and friendly demeanour, Michael had a front row seat for the formative years of modern Ireland.
"A Senior Counsel, he had a keen legal mind, and brought great wit, intelligence and determination to several ministerial roles spanning three decades.
"This experience was crucial whether serving as Minister for Foreign Affairs, Finance, Labour, Agriculture, Transport, Economic Planning and Development, or Public Service."
Mr Martin added: "Michael was also a strong voice for Ireland on the international stage, serving as European Commissioner in the early 1980s, before returning to the Dail to serve his beloved Tipperary North once again.
"He also served ably as a Senator, in 1965, and again from 1993 to 1997, in an extraordinary 37-year career in national politics.
"I want to express my deepest sympathies to the O'Kennedy family at this very difficult time, especially to his wife Breda and children Brian, Orla and Mary."