The Taoiseach last night said the suggestion, made by Mr David Trimble, to hold a referendum on reunifying Ireland was "premature" and that it would be a decade before debate on such a vote would even begin.
"I'm in agreement with those that believe that holding such a poll might be premature while we are involved in healing attitudes," Mr Ahern told an audience of students and faculty at Northwestern University in Evanston, a Chicago suburb.
"To force [reunification] is unwise. We have to stop people from literally killing each other," he said.
"I'm optimistic about the peace process in Northern Ireland," the Taoiseach said, praising British Prime Minister Mr Tony Blair and former US president Mr Bill Clinton for their efforts, "without which we would not be where we are," Mr Ahern said.
According to Mr Ahern, contacts are quietly increasing between Northern Ireland and the Irish Republic but trade between Belfast and Dublin is only one-third of what it should be. Mr Ahern said reunification would ultimately be smoothed by economic well-being.
In his speech, Mr Ahern did not mention Mr Trimble or Mr Adams by name.
In a separate appearance in Newport, Kentucky, Sinn Féin president Mr Gerry Adams repeated his support for a referendum on the North’s future.
Provisions for a poll on Northern Ireland's status were included in 1998's Belfast Agreement, but under the terms of the accord a subsequent vote could not be held for seven years.
Additional reporting