EUROPEAN UNION chief Brexit negotiator Michel Barnier issued new threats of a “hard border” with Ireland today if Britain leaves the single market.

The former EU commissioner also threatened to derail talks on a two-year “transition” period after Britain’s withdrawal from the bloc becomes final in May next year.

Following the latest round of talks with British Brexit Secretary David Davis, Mr Barnier said three “substantial” disagreements remained, warning: “if these disagreements persist, the transition is not a given.”