- Feb 1, 2017
(confusingly, it's not Merkel, but Macron on this photo)
After presenting the new proposals to Brussels, government sources hoped the UK might be able to enter an intense 10-day period of negotiations almost immediately, with the aim of coming to a final agreement at an EU summit on 17 October.
The EU pledged to examine them carefully, but a number of senior figures, including Irish Taoiseach Leo Varadkar, warned the proposals did not form the basis for deeper negotiations - even if they believed a deal could still be done.
French President Emanuel Macron said the EU would decide at the end of the week whether a new deal was possible.
But after the phone call on Tuesday morning, the No 10 source said it had been a "clarifying moment", adding: "Talks in Brussels are close to breaking down, despite the fact that the UK has moved a long way."
Under Mr Johnson's proposals, which he calls a "broad landing zone" for a new deal with the EU:
- Northern Ireland would leave the EU's customs union alongside the rest of the UK, at the start of 2021
- But Northern Ireland would continue to apply EU legislation relating to agricultural and other products, if the Northern Ireland Assembly approves
- This arrangement could, in theory, continue indefinitely, but the consent of Northern Ireland's politicians would have to be sought every four years
- Customs checks on goods traded between the UK and EU would be "decentralised", with paperwork submitted electronically and only a "very small number" of physical checks
- These checks should take place away from the border itself, at business premises or at "other points in the supply chain"
They also accused the EU of being "willing to torpedo the Good Friday agreement" - the peace process agreed in Northern Ireland in the 1990s - by refusing to accept Mr Johnson's proposals, arguing the plan is key to respecting the so-called "principle of consent".
But Mr Varadkar has warned the Johnson plan could actually undermine that principle by giving one party in Northern Ireland a veto over what happens to the country as a whole.
EU diplomats have told Adam Fleming there has been "zero progress" in the talks and in some areas they believe things are going backwards.
The UK's chief negotiator, David Frost, is still due to meet EU negotiators in Brussels today, but another European official said he had so little room for manoeuvre, it called into question whether the UK was serious about getting a deal.
On Monday night, the Spectator published texts from a Downing Street source, who claimed if the deal "dies in the next few days, then it won't be revived".
The government has not denied the briefing, which also said Mr Johnson "will do all sorts of things to scupper a delay" to leaving the EU.
Earlier, the BBC's political editor Laura Kuenssberg said there was a growing expectation in government Brexit talks would fail before the week was out.