Ursula von der Leyen warned that Brussels would not hesitate to hit Britain with tariffs if it failed to meet its commitments in Northern Ireland as MEPs prepared to ratify the Brexit trade deal on Tuesday.
The European Commission president said dispute and enforcement mechanisms in the deal were “essential” to ensure the UK complied with the trade deal and the Withdrawal Agreement, which includes the Northern Ireland Protocol.
France said the EU would retaliate and hit sectors such as financial services with tariffs if the UK did not properly implement the Brexit fishing agreement.
Mrs von der Leyen said, "This agreement comes with real teeth with a binding dispute settlement mechanism and the possibility for unilateral remedial measures were necessary. And let me be very clear. We do not want to have to use these tools, but we will not hesitate to use them if necessary.”
Britain angered Brussels by unilaterally extending grace periods in the Protocol and the European Commission has begun legal action against the UK. The grace periods exempt exports from Britain to Northern Ireland from customs checks on meat products and parcels. The UK has also carved out exemptions from EU rules on soil and pet passports.
Watch: EU will use trade tools on UK if needed
The trade deal has a level playing field dispute mechanism that can lead to tariffs being imposed if one side diverges too far from agreed common standards. The agreement’s enforcement measures also allow for retaliatory tariffs in a specific sector as a result of a dispute in another.
Mrs von der Leyen said that recent talks with the UK over the implementation of the Protocol had been "constructive" but added the trade deal's enforcement system would "focus minds" on finding solutions to the problems in the new customs arrangements for Northern Ireland.
Clément Beaune, France’s Europe Minister, said the Brexit deal was not a “blank check”, amid an ongoing row with the UK over fishing licences for French boats in the Channel.
“If the UK does not enforce it, we will respond with retaliatory measures,” he said.
The European Parliament branded Brexit a “historic mistake” as it debated a resolution, which criticised Britain over the implementation of the Northern Ireland Protocol and crowed about EU victories in the trade talks.
MEPs are expected to overwhelmingly back the trade agreement in the vote, which is the final step to conclude the years of Brexit negotiations begun with the triggering of Article 50 in March 2017.
The trade deal was provisionally applied at the end of last year because the negotiations ended so close to the no deal deadline. MEPs are unlikely to vote against the agreement because it would cause a no deal, which would be damaging for both sides.
The European Parliament resolution states, “the UK’s withdrawal from the EU is a historic mistake and recalls that the EU has always respected the UK’s decision while insisting that the UK must also accept the consequences of leaving the EU.”
It adds, “It is a logical consequence of the UK’s withdrawal from the EU and in particular the ending of freedom of movement, that the opportunities for the UK’s largely service-based economy are vastly reduced.”
The resolution accuses Britain of “depriving young people of such a unique opportunity” by refusing to continue participating in the Erasmus student exchange programme.
“Everybody has to shoulder the responsibility and respect what they have signed up to,” Michel Barnier, the EU’s former negotiator, said in a farewell speech.
Mr Barnier, who left the European Commission earlier this year, added, “This is a divorce. It's a warning, Brexit, and it's a failure. A failure of the European Union's, and we have to learn lessons from it.”
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