Video report by ITV News Europe Editor James Mates
It is unlikely a Brexit deal will be agreed tonight, a government source has said, despite speculation that negotiators were close to reaching one.
The source said it "feels" like there will not be a deal on Wednesday night, echoing reports from ITV News Political Editor Robert Peston that there's "no chance of Brexit deal" this evening.
But earlier in the day it had appeared as though a breakthrough was near, with French President Emmanuel Macron saying he wants "to believe that a deal is being finalised".
Boris Johnson needs to get a deal approved at the summit of EU leaders starting in Brussels on Thursday if he is to avoid an almighty clash over asking for a delay to the UK’s departure.
Video report by ITV News Political Correspondent Libby Weiner
His official spokesperson said the Prime Minister had on Wednesday afternoon updated his Cabinet, which gave its “full support” to get a deal ahead of the summit after a “positive discussion”.
“He said there was a chance of securing a good deal but we are not there yet and there remain outstanding issues,” the spokesperson added.
Peston understands MPs were told "almost nothing about what is being negotiated and the state of play."
Mr Johnson also updated the 1922 Committee of backbench MPs on how negotiations are going, as well as holding meetings with the pro-Brexit European Research Group (ERG) and Northern Ireland's Democratic Unionist Party.
During the 1922 address, Mr Johnson is said to have compared the situation to climbing Mount Everest.
Despite reports that a deal is not imminent, Chair of the ERG Steve Baker said he was "optimistic" a deal was near, after a meeting with the PM.
He said he hopes to be able to vote for Mr Johnson's deal but said he cannot confirm his intention until he has seen the document.
Also optimistic was fellow-ERG member Mark Francois who said "good progress" had been made, but "we're not quite there yet".
The Rayleigh and Wickford MP described talks between Mr Johnson and the ERG as "constructive" and said they had "moved forward".
Former Tory party leader Iain Duncan Smith agreed that talks had been "constructive" and the Government was "moving in the right direction".
He said they would "have to wait to see what comes back" from the negotiations in Europe, but he believed teams on the Continent are "getting quite close to a deal".
DUP leader Arlene Foster moved to reject a suggestion that her party had accepted the latest proposals in the deal regarding Northern Ireland consent issues.
She tweeted: "Discussions continue. Needs to be a sensible deal which unionists and nationalists can support."
According to Peston, a "Brexit deal now hinges on whether a consensus can be found" between the DUP, Ireland's Mr Varadkar and Mr Johnson on the PM's backstop alternative.
The EU's chief negotiator Michel Barnier has briefed EU ambassadors, ahead of Thursday's summit.
ITV News Political Editor Robert Peston on what the chances are of a deal
Following the meeting, EU commissioner Dimitris Avramopoulos said: "Talks have been constructive but there still remains a number of significant issues to resolve."
Earlier on Wednesday, Irish Taoiseach Leo Varadkar had said he was "confident" a deal could be struck, following a phone call with the Prime Minister.
But he warned there are still numerous hurdles in the way of a deal after speaking with Mr Johnson and the European Commission on Wednesday morning.
"There is a pathway to a possible deal but there are many issues that still need to be resolved, particularly around the consent mechanism and issues around customs and VAT," he said.
ITV News Europe Editor James Mates on what is likely to happen next
Meanwhile, Labour leader Jeremy Corbyn said he's "deeply concerned" about the ongoing negotiations and claimed the deal is unacceptable, based on what he knows of it.
Mr Corbyn also criticised the PM for spending too much time negotiating with the EU and his own party and not enough time in Parliament.
One of the Labour leader's main fears is that the Prime Minister will ignore legislation which demands he requests a Brexit extension if a deal isn't reached and leaving with no deal has not been approved.
However, Brexit Secretary Stephen Barclay again confirmed that Mr Johnson will write a letter requesting a Brexit delay from the EU if a deal has not been reached by Saturday.
Mr Barclay said the Prime Minister would request the extension - as he is directed to by the so-called Benn Act - but suggested it may be possible to both send the letter and leave by the deadline.
"I can confirm, as the Prime Minister has repeatedly set out, that firstly the Government will comply with the law, and secondly it will comply with undertakings given to the court in respect of the law," he said.
When asked how the Government plans to leave the EU after promising to request an extension, he said there are a "number of variables that apply to what is a complex piece of legislation".
He said the best way to avoid requesting a delay would be to reach an agreement and claimed the "full effort of government is focused on that".