The EU’s chief negotiator’s remarks came after Boris Johnson held a phone call with Ursula von der Leyen to discuss the state of play, with the European Commission president concluding there were still “big differences” preventing a deal.
Downing Street said the prime minister had emphasised during the conversation that talks were “now in a serious situation” and said that it “now looked very likely that an agreement would not be reached unless the EU position changed substantially”.
In an address to the European Parliament on Friday, Mr Barnier said that while there is a “chance” of London and Brussels securing a deal, “the path to such an agreement is very narrow”.
On the ongoing negotiations, Mr Barnier told MEPs: “It’s a question of whether the UK will leave in a few days, 10 days or so, if they are going to leave the single market, the customs union, with an agreement, or without an agreement.
“It’s the moment of truth. We have very little time remaining, just a few hours to work through these negotiations in a useful fashion if we want this agreement to enter into force on 1 January.”
With just 13 days to go until the end of the transition period, the bloc’s chief negotiator said: “The unresolved issues in these few crucial hours that remain at our disposal are fundamental issues for the European Union.”
"We're not asking more nor less than a balance between rights and obligations and reciprocity, access to our markets and access to our waters and the other way round, no more, no less.
"It's also obvious that this isn't an agreement we will sign at any price or any cost,” he added.
"I think I've always been frank with you and open and sincere. I cannot say what will come during this last home straight of negotiations. We have to be prepared for all eventualities."
Detailing the key issues preventing progress in the talks, Mr Barnier said the “negotiations have been extremely difficult”, adding: “We’ve reached the hard nuts to crack.”
Describing fishing rights after the Brexit transition period as “one of the main hurdles” in the negotiations, he went on: “I don’t think it would be fair nor acceptable if European fishermen were not allowed following transitional rights to have access to those waters when the rest of the agreement, especially applying to companies from the UK, would remain stable.
"That wouldn’t be fair, that wouldn’t be honest.”
Schools minister Nick Gibb, who was doing the government’s morning broadcast round on Friday, said that Britain was “working around the clock” to secure a trade deal with the bloc, telling Times Radio: “The prime minister says that we are in a very serious situation.
“"We will test every route to getting a free trade agreement before the end of the year. But we can't do so at the expense of our sovereignty. We cannot be the only nation in the world that doesn't have control of its own seas, its own fisheries.
"So, we will work very hard. The government is working around the clock to get a trade deal, but not at the expense of this country's independence."
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