Brussels has also threatened to take action if the UK takes the unilateral decision to delay imposing checks on chilled meats in Northern Ireland, which are due to come into force at the end of June.
Speaking in London after the meeting, Mr Sefcovic said negotiations had reached a “cross roads”.
He added: “Trust, which should be at the heart of every partnership, needs to be restored.”
His remarks about trust triggered a furious response from a number of Express.co.uk readers who let their feelings known in the comments section of an earlier story.
Several users pointed out the record of the bloc was far from perfect and highlighted the move by Brussels to stop Oxford-AstraZeneca vaccines being shipped from Europe into the UK earlier this year.
One user wrote: “’You stole life-saving vaccines!”
A second added: “Trust works both ways. Just look at the EU and its AZ vaccine fiasco.”
A third commented: “How funny coming from the completely unfit for purpose untrustworthy EU.”
Meanwhile, a fourth said: “And they say they don’t trust the UK, wow that’s rich coming from a dictatorship disguised as the European Union.”
The Northern Ireland Protocol was created to protect the Good Friday Agreement and the integrity of EU markets.
Boris Johnson suggested the European Union is taking an “excessively burdensome” approach to the Protocol.
He explained there was now three times as many checks in Northern Ireland than in Rotterdam.
The Prime Minister downplayed the prospect of the UK moving further away from the deal, but insisted the UK’s “internal market” had to be respected and “we just need to make it work”.