Paddy Harte, the former Fine Gael TD for Donegal North East from 1961 to 1997, has died.
Mr Harte, who was 86, was a minister of state at the Department of Posts and Telegraphs between 1981 and 1982.
In 1998, he received the European of the Year award for his work in developing a Peace Park at Messines in Flanders to commemorate the estimated 50,000 Irish people who died during World War I.
The former taoiseach John Bruton paid tribute to the life and political career of Mr Harte.
He said: "He quickly earned a reputation as an original, independent minded, individual who thought for himself about the political questions of the day.
"He was a resolute opponent of republican political violence. Working with Glenn Barr, he sought reconciliation between Nationalists and Unionists on the island, notably through the joint commemoration of the sacrifices both communities made during the First World War.
"This was often a lonely path for him to follow, and he showed great physical and moral courage."
Government Chief Whip Joe McHugh said Mr Harte had left a lasting peace process legacy through his cross-community and cross-border work.
"He did incredible work to build bridges on this island during many dark days for our people.
"His lasting legacy will be the Island of Ireland Peace Park in Flanders, Belgium, which was officially opened by President McAleese in 1998," he said.
Tánaiste Simon Coveney paid tribute to Mr Harte, describing him as a "proud Donegal man and an exceptionally committed public representative".
He said: "Paddy Harte's tireless work as a public representative and his vision and commitment to peace and reconciliation deserves to be long remembered."
Fianna Fáil Leader Micheál Martin described Mr Harte as a tireless worker and a popular TD.
He said: "It is probably for his involvement in promoting the recognition of Irish people who died during World War I that he will be best remembered.
"His determination to progress this issue not only acknowledged the sacrifice that Irish soldiers made in the First World War, it led to the construction of the Island of Ireland Peace Park and Round Tower in Belgium.
"This work saw him awarded numerous accolades including an Honorary OBE and an Honorary Doctorate of Laws from the National University of Ireland."