The Government has confirmed that it will seek a declaration by all European Union member-states that the Nice Treaty will not affect Ireland's military neutrality.
The Minister for Foreign Affairs said that consultations would begin at Friday's EU summit in Barcelona, with the aim of securing agreement when leaders meet in Seville in June.
Mr Cowen expressed confid-ence that such a declaration would persuade voters to back the treaty in a second referendum.
He said some voters had been persuaded by campaigners against the treaty that it would compromise neutrality - a claim which, he said, was without foundation.
"The Government's intention will be to reassure those who have raised concerns on these matters," he said.
A declaration by the member-states could refer to other issues apart from neutrality, he added.
But he ruled out asking the other member-states to agree not to implement a clause in the treaty that would limit the number of commissioners once the EU has 27 members.
Two former Commission officials, Prof John Temple Lang and Mr Eamonn Gallagher, have told the Forum on Europe that ending the automatic right of each member-state to a commissioner would damage the EU's institutional balance.
Their proposal has won some support in political circles, and one EU head of government is understood to be convinced of its merits.
But Mr Cowen said that reopening the issue could lead to a worse deal for small member-states.
He claimed that the Nice Treaty reflected the interests of smaller countries.
"The negotiating achievements of the small states have often not been highlighted," he said.
Mr Cowen said that, although a declaration on neutrality could reassure voters about the treaty, there was no need to enshrine Ireland's non-aligned status in the Constitution.
