Former British prime minister Sir Edward Heath will be remembered "with particular affection" in Ireland, the Taoiseach said this morning.
Sir Edward died last night at his home in Salisbury at the age of 89. He had been able to host a party last week in celebration of his 89th birthday, but his spokesman said he had "recently become considerably weaker".
In a statement this morning, Mr Ahern expressed his sadness at the death of the former Conservative Party leader, who he said had a "long and distinguished career in British parliamentary politics spanning over 50 years".
"Sir Edward will be remembered with particular affection in Ireland because it was he who negotiated the Sunningdale Agreement of 1974 which in many ways was the model for every subsequent effort to bring about peace and stability on the island of Ireland."
Former Conservative leader Margaret Thatcher, the long-term adversary who ousted Sir Edward as Tory leader in 1975, hailed him as a "political giant" and "the first modern Conservative leader".
Queen Elizabeth, Prime Minister Tony Blair and Tory leader Michael Howard also paid tribute to Sir Edward, who occupied 10 Downing Street from 1970 to 1974.
The veteran politician suffered a pulmonary embolism while holidaying in Austria two years ago and never seemed to recover fully. He had been "resting quietly" at the home in Salisbury, Wiltshire, when he passed away at 7.30pm.
Although in Downing Street for less than four years, his legacy is assured as the prime minister who persuaded Britain to join the European Economic Community.
He will be equally remembered for his long feud with Baroness Thatcher, who defeated him in a Tory leadership contest. His reaction was memorably described as the "longest sulk in history".
Sir Edward entered the British parliament as an MP in February 1950 and only stood down at the 2001 election, 11 years after becoming Father of the House, the longest continually serving MP.
Additional reporting: Agencies