It will be "practically impossible" to deal with the unresolved issues in the peace process if they are not addressed before midsummer, according to the Taoiseach, Mr Ahern.
Speaking to reporters yesterday after the annual Fianna Fail 1916 commemoration at Arbour Hill in Dublin, Mr Ahern said there was now a "tight time-scale" to deal with these matters.
Initially, the British general election was expected on May 7th, he said, leaving time after the poll and before the marching season to tackle outstanding matters. But with the election postponed and another Drumcree confrontation looming in early July, time was short.
"There are a number of outstanding issues which we have to try to come to grips with," he said.
"Decommissioning is one. The suspension of the two ministers in the Executive [from meetings of the North-South Ministerial Council] is a second one, and trying to find a full resolution on policing is a third. These are issues we have to work on, even during the election period, as best we can."
However, he said he did not share the view of Mr David Trimble that the Belfast Agreement faced collapse if these issues were not resolved shortly.
"The agreement is strong", he said. "Foot-and-mouth has been an awful dilemma for the island, particularly for our Northern colleagues over the last few weeks. But it has also shown the strength of a devolved administration and how people can work together."
He said co-operation was also bringing investment to Northern Ireland, and the new US administration was putting great emphasis on economic development. "All of that is very positive, but we must not allow things to drift. If we come up against these difficult issues in late or midsummer it will be practically impossible to deal with them."
Mr Ahern also voiced Government concern about the proposed introduction of a new form of plastic bullet in Northern Ireland.
"The clear spirit of the Good Friday agreement and the Patten report is that they should be phased out, not renewed or replaced in a different form."
In the North yesterday, the RUC Chief Constable, Sir Ronnie Flanagan, warned the Real IRA was growing in strength. He compared the strength of the group with that of the Provisional IRA in the early 1970s. He said the "Real IRA" had only failed to kill people recently as a result of police action and "the grace of God".