RUTH Davidson has thrown her weight behind Boris Johnson’s Brexit project, as she insisted her resignation was purely personal and not political.

The Scottish Tory leader, who gave birth to her son Finn last October, said yesterday she believed the Prime Minister was genuinely trying to agree a deal with Europe.

Johnson’s controversial decision to prorogue of Parliament was, she added, an opportunity for MPs to vote for a Brexit deal.

In a letter to Robert Forman, the party’s chairman in Scotland, Davidson said she would stay on as the MSP for Edinburgh Central until 2021, but wanted to spend more time with her family and less time leading the party’s election efforts.

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“I have to be honest, where once the idea of getting on the road to fight two elections in 20 months would once have fired me up, the threat of spending hundreds of hours away from my home and family now fills me with dread,” she said. “That is no way to lead.”

She added: “I fear that having tried to be a good leader over the years, I have proved a poor daughter, sister, partner and friend.

“The party and my work has always come first, often at the expense of commitments to loved ones. The arrival of my son means I now make a different choice.”

Her resignation – effective immediately – means the party could now be forced into fighting a snap General Election with no leader.

Jackson Carlaw is to step up as interim leader and will lead the Scottish Tories at next Thursday’s First Minister’s Questions.

The National:

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Davidson’s spokesman told journalists that she had first voiced doubts about the job after May’s European election when the Tories finished in fourth place in Scotland behind the Brexit Party and the LibDems. He said she had spent the summer considering her position and had decided to quit ahead of Holyrood’s return from recess next week.

He insisted the timing – leaking on the day the Government prorogued Parliament – was coincidence, and that Thursday’s press conference had been in the planning since Monday.

Davidson had often been tipped as a future prime minister – though she always insisted her ambition was to be first minister.

In a press conference, the Tory said her proudest achievement was campaigning against independence.

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“For me, electoral successes – while undoubtedly important – pale in significance compared to the vital role our party undertook as part of the campaign to keep Scotland in the United Kingdom at the independence referendum.

“It was – without doubt – the most important contribution of my working life and, I believe, will remain so.”

After Johnson became Prime Minister, Davidson said she could not support him if he pursued a No-Deal Brexit.

Writing in the Mail on Sunday at the time, she said: “I don’t think the Government should pursue a No-Deal Brexit and, if it comes to it, I won’t support it.”

The MSP, who was close to Theresa May, was said to be livid when Johnson ignored her advice and sacked David Mundell as secretary of state for Scotland, replacing him with Alister Jack.

Yesterday, the Prime Minister paid a fulsome tribute to his outgoing Scottish party leader, saying he was “delighted she will continue to use her passion and dedication to make the case for Scotland’s place in the UK from the backbenches and beyond”.

He added: “She should take immeasurable pride in the pivotal role she played during the Scottish independence referendum campaign.”