It comes after an apparent Brexit breakthrough on Thursday when the Prime Minister held crunch talks with his Irish counterpart Leo Varadkar.
Since voting to leave the EU back in 2016, Britain has struggled to come up with a way to exit that is acceptable to both their people and the union.
The discussions focused heavily on the issues of the customs arrangements and the proposed "consent" mechanism for the Northern Ireland Assembly.
He said the United Kingdom had yet to put forward an "operational, legally binding solution" to replace the Northern Ireland backstop - meant to prevent the return of a hard border with the Republic.
It's similar to a "customs partnership" plan the European Union rejected in 2018, and would leave Northern Ireland with a different customs regime to the rest of the U.K. British authorities would have to collect tariffs on behalf of the bloc on goods crossing the Irish sea.
But any concession that would keep Northern Ireland in the customs union would cause a political storm within the Conservative Party, and it is unclear whether there would be a majority in Parliament for such a deal.
UK Brexit secretary Stephen Barclay, right, shakes hands with European Union chief Brexit negotiator Michel Barnier before their meeting at the European Commission headquarters in Brussels, Friday, Oct. 11, 2019.
But Brussels has said it will not accept the proposal on the grounds that it would require customs checks on the island of Ireland, which it says would threaten the Irish peace settlement.
With the British Parliament and government both rejecting the withdrawal treaty negotiated by Theresa May, and the European Union rejecting a rehash of the treaty with some alternative arrangements for the customs border between EU member-state the Republic of Ireland and the British province of Northern Ireland put forward by Boris Johnson, the United Kingdom is now headed for a clean break with the bloc - or, if anti-Brexit MPs have their way, yet another Brexit delay.
He said there was not "a done deal", adding: "The best thing we can do now is let our negotiators get on with it". "There's work to be done".
Support from DUP MPs could be crucial to get a deal through Parliament. The group is staunchly opposed to the region being subject to different customs rules to the rest of the United Kingdom. "If there is a will, there is a way" she said.
Negotiators were dispatched for talks in Brussels on Friday, with reports suggesting their success paved the way for an entry into the "tunnel" phase of intensive and secretive discussions.
However, after the "constructive" breakfast with Barclay, Barnier was given the go-ahead from member state ambassadors to begin a more detailed negotiation on a path towards a possible draft text.
For all the fresh optimism, there is still a long way to go.