Scottish first minister Nicola Sturgeon surprised May two weeks ago by calling for a second independence vote before Brexit takes place.

Sturgeon argued that the interests of Scotland, which voted overwhelmingly to remain in the EU in last year’s UK referendum, were not being taken seriously by May.

Scotland, for instance, wanted to remain in the single market, as the whole of the UK will cease its membership.

The Scottish parliament is expected to back the call for the plebiscite on Tuesday, even though it still needs London’s approval to go ahead.

The British PM has already said, she disagrees with the timing of the independence bid.

That lead to a tough war of words between the two leaders with Sturgeon arguing it was “undemocratic” for London to refuse the referendum.

On Monday, May said again that she would not allow it go ahead on Scotland’s timetable.

Before meeting Sturgeon, May said she wanted a “more united nation” and that she would fight for the interests of all parts of Britain.

She reiterated that it was “not the time” for the Scottish referendum and that it would be unfair to voters to decide on something before all the facts of Britain's terms of exit from the EU were known.

Sturgeon had called for the referendum to come at the end of 2018 or beginning of 2019, before the two-year EU negotiating period expired, and the UK automatically became a “third country”.

But May said in a speech to aid and development officials in East Kilbride that "Now is the time when we should be pulling together, not hanging apart. Pulling together to make sure we get the best possible deal for the whole of the UK."

She also argued that together the UK would be an “unstoppable force”.

She said her government would respect and stregthen the devolution settlements, but would never allow the "Union to become looser and weaker, or our people to drift apart"

Norther Ireland debacle

May’s government is at the same time scrambling to urge parties in Northern Ireland to reach a deal on the regional government In Belfast.

Sinn Fein, which won the election earlier this month, has called for a Scottish-type independence vote.

Northern Ireland also voted for the UK to remain in the EU.

The future status of its frontier with the Republic of Ireland, where border controls could return once the UK leaves the EU, is a key issue in the Brexit talks.