dublin likely european union leaders allow brexit talk move onto trade relations december long britain provide guarantee write issue currently debate ireland prime minister say wednesday eu engage britain future trade relationship post-brexit transition period work london wish first ongoing round divorce talk sufficiently progress brussels want three issue broadly solve give green light exit bill safeguard expatriate right border ireland northern ireland uk land frontier eu departure view likely able say sufficient progress make december eu leaders meet allow us move onto discussions transition future arrangements prediction stage leo varadkar tell parliament course depend happen next number weeks specific assurances guarantee write get unite kingdom varadkar say optimistic number weeks ago talk move right direction strike positive tone foreign minister simon coveney say recently dublin could let talk progress without clarity border irish government call britain simply promise hard border return northern ireland 1998 peace deal separate military checkpoints 30 years sectarian violence british province eu diplomats officials tell reuters tuesday continue slow pace divorce talk increase possibility eu leaders would refuse next month open trade talk say may already consider useful tactic britain anxious prevent businesses relocate investment go possible fully resolve border question actually start talk future relationship uk northern ireland come point interest actually start talk varadkar say irish pm see brexit talk move next stage december