Boris Johnson is to hold talks with European Commission president Jean-Claude Juncker as he continues his efforts to find a new Brexit deal.
The Prime Minister will travel to Luxembourg on Monday for his first meeting with Mr Juncker since entering Number 10 in July, Downing Street said.
Number 10 sources played down the prospect of an imminent breakthrough however, insisting there was still “a long way to go”.
Earlier, Irish premier Leo Varadkar warned that the gap between the two sides on the crucial issue of the Northern Ireland backstop was still “very wide”.
“We have always said we would be willing to look at alternative arrangements, but what we’re seeing falls far short,” Mr Varadkar told RTE radio.
“We are exploring what is possible. The gap is very wide but we will fight for and work for a deal until the last moment, but not at any cost.”
Mr Johnson’s meeting with Mr Juncker follows talks with other key EU players including Mr Varadkar, German Chancellor Angela Merkel and French President Emmanuel Macron.
A European Commission spokeswoman said Mr Juncker was “looking forward to working constructively” with the Prime Minister.
She said the talks, over a working lunch, would be held at a “neutral location” rather than the British Embassy or a commission venue.
Mr Juncker will then address the European Parliament in Strasbourg on Wednesday on the progress in the negotiations.
“By common accord they agreed to meet in Luxembourg on Monday,” the spokeswoman told a briefing in Brussels.
“They have been trying to arrange a meeting for a while now. They’ve already spoken on the phone, so I think it’s the willingness that comes from both sides.”
Earlier, DUP leader Arlene Foster dismissed reports that her party was ready to help Mr Johnson get a deal by softening its Brexit “red lines”.
The Times reported the DUP was prepared to accept some EU rules after Brexit as part of a new agreement to replace the backstop – intended to ensure there is no return of a hard border with the Republic.
It said the party was ready to drop its objections to regulatory checks between Northern Ireland and the rest of the UK – something it has vehemently resisted.
However, Mrs Foster said they remained opposed to what would amount to a Northern Ireland-only backstop with a border in the Irish Sea.
“UK must leave as one nation. We are keen to see a sensible deal but not one that divides the internal market of the UK,” she tweeted.
“We will not support any arrangements that create a barrier to East West trade. Anonymous sources lead to nonsense stories.”
The support of the DUP’s 10 MPs – who helped prop up Theresa May’s government – is likely to be crucial if Mr Johnson is to get a new deal through the Commons.