British Prime Minister Boris Johnson plunged Brexit into chaos earlier this month by unveiling, and then pressing ahead with, draft legislation that would undercut parts of the 2020 EU divorce treaty relating to Northern Ireland.

"Why would the EU ratify a new agreement with a country that is threatening to break an agreement that's not even 12 months old," Coveney, who played a major role in shaping the divorce treaty, told Ireland's parliament.

(Reporting by Padraic Halpin; Editing by Toby Chopra)