Brexit talks have continued through the night as hopes were raised that a trade deal could finally be on the brink of being agreed.
Sources in London and Brussels told Sky News on Wednesday evening that an agreement could be close.
Eric Mamer, the chief spokesman for the European Commission President Ursula von der Leyen, tweeted to say "Brexit work would continue throughout the night".
He added: "Grabbing some sleep is recommended to all Brexit-watchers at this point.
"It will hopefully be an early start tomorrow morning."
A late night delivery of pizzas was earlier seen being dropped off at the European Commission headquarters in Brussels.
Meanwhile, Sky News understands a call to Boris Johnson's cabinet took place late last night to update them on the state of play in the talks.
Britain left the EU at the end of January and entered into an 11-month transition period, following EU rules and regulations whilst trying to negotiate a free trade deal by the end of this year.
But a number of sticking points have emerged during the negotiations, raising the prospect of a no-deal Brexit.
These include fishing rights and the so-called "level playing field" - measures to prevent what is seen as unfair competition through the lowering of standards or the use of state subsidies.
The PM has acknowledged that a no-deal Brexit "may be difficult at first", but has maintained that the UK would "prosper mightily" under such a scenario if it comes to pass.
But opponents say leaving without a deal and consequently having to trade on World Trade Organisation terms from 1 January would cause problems for business and push up prices for consumers.
Both sides had set a deadline of mid-October for reaching a trade deal, with the expectation it would then take time for the final version to be scrutinised and voted on.
Parliament needs to ratify a deal if one is agreed, but it has already broken up for Christmas.
However, Sky News has been told MPs could be recalled on 30 December to approve any last-minute agreement.
A senior EU diplomat told the Reuters news agency on Wednesday that a provisional application of a deal would need to be approved by member states because there is not enough time for the EU Parliament to ratify a deal.