The negotiations between Britain and the European Union over their future relationship are lurching toward a crisis after European Union leaders told Boris Johnson he must make concessions only hours before the prime minister is due to decide whether to walk away.
David Frost, the UK's chief Brexit negotiator, said he was surprised and disappointed at the warning, which came during a summit of EU leaders on Thursday. He said that Johnson, who has threatened to quit the negotiations at the end of this week if a deal can't be struck, would respond on Friday.
The spat is a sign that the seven months of negotiations between the two sides over their future relationship are heading for what could be a key turning point.
Without an accord, millions of businesses and consumers will face additional costs and disruption when Britain leaves the single market on Dec 31.
If conditions aren't met, it's possible we won't have an agreement, French President Emmanuel Macron said as he arrived at the summit in Brussels. We are ready for that. But there is still time - just - for the two sides to clinch a deal.
The UK had been calling on the EU to agree to round-the-clock negotiations to push through an agreement within the next two weeks.
But for Johnson to be persuaded to stay at the table, negotiators had wanted to see positive signs from the bloc, including a signal it was willing to intensify negotiations - something they pointedly refused to do.
Surprised EU is no longer committed to working intensively to reach a future partnership, Frost said in a tweet.
Also surprised by suggestion that to get an agreement all future moves must come from UK. It's an unusual approach to conducting a negotiation.