BRUSSELS (Reuters) - The European Union’s Brexit negotiator told the 27 national envoys to Brussels on Wednesday that differences in UK trade talks persisted, according to a senior EU diplomat who was present at the closed-door briefing. “Differences still persist on the three main issues,” the diplomat said, when asked for the overall thrust of Barnier’s update to EU member states on the latest in Brexit trade talks. “A deal still hangs in the balance.” Reporting by John Chalmers, Writing by Gabriela Baczynska, Editing by Catherine Evans