brussels european union brexit negotiator michel barnier assure ireland foreign minister friday eu would defend dublin position talk britain come weeks barnier say twitter update simon coveney state play negotiations britain hop clinch deal brussels next month range issue include management northern irish border order launch second phase discussions focus trade accord strong solidarity ireland barnier write irish issue eu issue coveney tweet back thank michelbarnier reaffirm eu solidarity ireland brexit face possible government collapse new elections crucial point brexit process irish government sharpen tone demand london detail border keep open unhindered warn veto move trade talk satisfy barnier reassure ireland eu stand dublin brexit