Coveney stressed that the implementation of agreements that have already been struck is a test of good faith and trust | John Thys/AFP via Getty Images Irish deputy PM: Even basic Brexit trade deal at risk if UK tries to evade customs checks Simon Coveney responds to reports of London trying to ‘get around’ Northern Ireland protocol.

British attempts to evade checks on goods in the Irish Sea would "significantly" damage the prospect of reaching even a basic EU-U.K. free-trade agreement by the end of the year, Ireland's deputy prime minister warned Tuesday.

The comments from Simon Coveney, who spoke to reporters ahead of a meeting of EU ministers in Brussels, where they adopted the bloc's negotiation mandate for trade talks, came in reaction to reports that British Prime Minister Boris Johnson's Brexit team has been ordered to come up with plans to "get around" the Northern Ireland protocol in the Brexit Withdrawal Agreement, which foresees checks on goods passing from Britain to Northern Ireland.

“The Withdrawal Agreement involves significant commitments in the context of Northern Ireland through that Irish protocol that both the EU and the U.K. need to follow through on," Coveney said. "If that doesn’t happen then I think it will damage significantly the prospects of being able to get even a barebones trade agreement, along with a number of other things that need to be done in place by the end of the year.”

Coveney, who said he had just met EU chief Brexit negotiator Michel Barnier to discuss the issue, stressed that "in some ways the implementation of agreements that have already been struck is the test of good faith and trust. And without good faith and trust, building a future relationship is not going to be easy."

He added: "Just to be clear, Michel Barnier and the Irish government are at one on this.”

French EU Minister Amélie de Montchalin also had fighting words for London. She told reporters outside the General Affairs Council meeting that “mutual confidence” is essential for the negotiations. “To make new commitments, to sign a new agreement, it must be clear that what we did so far — that’s to have a first agreement, the Withdrawal Agreement — must be fully respected," she said. "We cannot restart negotiations if what we agreed some months ago is not being correctly implemented.”

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