Sir Robert Buckland, former Wales secretary and justice secretary, told Sky News it "does look like the British government and the EU have agreed a deal".

Meanwhile, Labour leader Sir Keir Starmer reaffirmed his party's support for an enhanced deal, saying "we've been working on these problems for a very, very long time and know what some of the solutions are."

Prime Minister Rishi Sunak has been in talks with the EU over the past few weeks to try to settle the significant issues the Northern Ireland Protocol has brought for trade in the nation after the UK left the EU three years ago.

He and European Commission President Ursula von der Leyen are set to make an announcement this afternoon if a final deal can be agreed following further talks today.

Final talks on post-Brexit deal - live politics updates

Sir Robert, who is on the Commons' Northern Ireland affairs committee, told Sky News' Kay Burley at Breakfast programme: "We mustn't let the perfect be the enemy of the good.

"I'm sure that this deal will probably have some unanswered questions and maybe not solve all the issues in one fell swoop.

"But it does sound as if it's going to be a big step forward."

He added that if that is the case the government will not have to take "unilateral action", in reference to the Northern Ireland Protocol Bill introduced by Boris Johnson that rode over the deal he agreed with the EU but has been paused by Mr Sunak.

Read more:
What is the Northern Ireland Protocol and why does it matter?
How today's Brexit talks between Sunak and von der Leyen could unfold

On why Mr Sunak appears to have got further than his three predecessors in agreeing a deal that benefits both the EU and the UK, Sir Robert said: "This prime minister has been able to create a relationship of trust.

"I think it's about personalities, this isn't a reflection on previous prime ministers but if you get on well with people and win their trust then I think, in all our experiences, more business can be done.

"I think the relationship with the French president has probably improved, I think there is that willingness."

Will there be a vote on the deal?

Both Tory and Labour MPs have been given a three-line whip for today, meaning they face suspension from their parties if they do not turn up in parliament.

This has prompted speculation there will be a vote by MPs on the expected deal.

Sir Robert said there "technically" does not have to be a vote because the EU Withdrawal Act allows for deals to have a "direct effect".

However, he said: "I think there'll be some sort of vote."

Liberal Democrat leader Ed Davey also said he expects there will be a vote.

"He doesn't need to take it to parliament, he doesn't absolutely need to in terms of the constitution," he told Sky News' Kay Burley at Breakfast.

"But I think politically he needs to, I think most MPs, if not all MPs, and certainly voters would think it extraordinary for him to do this huge deal and not allow the electorate anticipating his representatives to have a say."