Nicola Sturgeon accused the UK government of failing to come up with coherent plans for Brexit.

The Scottish first minister said talks at Number 10 on Monday were "frustrating" and she was left "no clearer" about how the Government will pull Britain out of the EU despite two hours of discussions.

Asked if she was undermining the UK position, she told the Guardian "You can't undermine something that doesn't exist."

The leaders of Scotland, Wales and Northern Ireland were all invited to the talks at Downing Street by Theresa May, who has tried to quell their fears over her handling of the situation.

But the leaders of the devolved states said they remained concerned that the UK was blundering towards an exit with time to agree on any deal with the EU fast running down.

The Welsh First Minister Carwyn Jones said that leaders had got no details about what happens next in the divorce talks, and warned "time is not on our side".

Downing Street warned against 'undermining' UK negotiations with the EU. Credit: PA

Scotland, which voted to stay in the EU, has also announced that it will bring shortly forward its own plans for a so-called flexible Brexit which would keep the country in the single market even if England chooses to leave.

Their vocal concerns over the process have caused tension with the main UK government.

Theresa May invited the devolved states to get involved in formal talks on Brexit - but officials have also urged the leaders not to "undermine" work on negotiations with Europe.

"We have been very clear that we should be working together to secure the best possible deal for the whole country," the Prime Minister's official spokeswoman said.

"We expect representatives of the devolved administrations to act in that way and to in no way undermine the UK's position."