The EU will decide at the end of the week whether a Brexit deal is going to be possible, French President Emmanuel Macron has told Boris Johnson.
President Macron said talks should now proceed swiftly to see if an agreement could “respect” EU principles.
Mr Johnson said the EU should not be “lured” into thinking there would be a delay to Brexit beyond 31 October.
The PM will hold further calls with EU leaders on Monday to discuss his latest proposals for the Irish border.
Downing Street said Mr Johnson was expected to hold phone calls with the leaders of Sweden, Denmark and Poland, after speaking to Mr Macron on Sunday.
The prime minister told the French president over the phone he believed a deal could be achieved, but that the EU must match compromises made by the UK.
A French government official said President Macron told Mr Johnson “that the negotiations should continue swiftly with Michel Barnier’s team in coming days, in order to evaluate at the end of the week whether a deal is possible that respects European Union principles”.
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The comments come ahead of a key few days of negotiations as both parties try to find a new agreement in time for a summit of European leaders on 17 and 18 October.
On Monday, Mr Johnson’s Europe adviser, David Frost, will hold further discussions with the European Commission, while Brexit Secretary Stephen Barclay will visit EU capitals.