DUBLIN/BELFAST (Reuters) - The Irish government on Monday said an agreement that would leave Northern Ireland within the European Union's customs union after Britain leaves the EU was "legally firm," but Northern Ireland's largest party said the issue remained open for debate.
The future of Ireland's border with Northern Ireland - which will be the EU's only major land border with Britain after Brexit - was widely seen as the biggest obstacle to an agreement on a 21-month transition deal to avoid a "cliff edge" Brexit.