REVELATIONS that David Cameron became intensely frustrated at Theresa May’s unwillingness to declare her position in the run-up to the EU referendum campaign, show the “breath-taking recklessness” of the Tory government’s decision to stage the Brexit vote, a senior SNP figure has claimed.

SNP MSP Stewart Stevenson accused Cameron, May and other Tory ministers of playing “parlour games” that have led to Scotland facing the prospect of being pulled out of the European Union against its will.

The scathing remarks from the former minister came after Cameron’s former communications chief, Sir Craig Oliver, said May failed to support the then PM on 13 separate occasions over his Remain stance.

Oliver claimed that May did reluctantly “come off the fence” for Remain, but only after a “visibly wound-up” prime minster gave her a dressing down over the telephone.

In his book, Unleashing Demons: The Inside Story Of Brexit, Oliver lays bare the extent of the tensions between May and Cameron, who earlier this month quit as an MP in a move widely viewed as being linked to his political differences with his successor in Downing Street.

The former Tory spin doctor also describes Boris Johnson’s “flip-flopping” during the weekend he finally came out in support of Brexit.

Oliver said that the day before he made the announcement putting himself at the head of the Vote Leave campaign, the former London mayor warned Cameron in a text he would be campaigning for Out, only to send a second text suggesting he could change his mind.

The former spin chief said May’s unwillingness to declare her hand in the run-up to the campaign had caused frustration in No 10, but he admitted that her low-key approach served her well in the aftermath of the vote for Brexit.

“Amid the murder and betrayal of the campaign, one figure stayed very still at the centre of it all – Theresa May. Now she is the last one standing,” he wrote.

Stevenson said the account from Oliver was proof that the decision to hold the In-Out referendum and the conduct of senior ministers on both sides of the Brexit divide was driven by internal Tory divisions over Europe rather than the national interest.

The SNP MSP for Banffshire and Buchan Coast said the consequence of such divisions meant that Scotland faced being pulled out of the EU after being outvoted by the UK as whole in the referendum on June 23.

Stevenson said: “These revelations prove what we already suspected – that the Brexit campaign was an exercise in breath-taking recklessness.”

He claimed the Tories “were more concerned with their personal ambitions and cabinet rivalries than about the interests of people, business and the country.

“It is disgraceful that these Downing Street parlour games have led to the prospect of Scotland being dragged out of the EU against our will – although it is now clear why the Tories are utterly clueless about what Brexit actually means.”

Oliver describes one conversation with Cameron in January after the then Tory leader had sought to sound out May – who was then home secretary – about her views on the EU.

“It sounds like she refused to come off the fence. From her point of view, it’s a smart strategy, trying to demonstrate she is her own person, allowing her to have her cake and eat it, but it doesn’t seem fair on DC, who has treated her well,” he wrote.

“Her sphinx-like approach is becoming difficult, with the press questioning which way she will jump. The conversation turns around this being the biggest thing the PM has faced and him not even knowing if the home secretary is backing him,” he wrote.

Oliver also describes how the day before he came out for Brexit, Johnson sent a text to Cameron warning him that he would be campaigning for Leave, only to send a second message suggesting he could back Remain.

“I ask DC what makes him so sure Boris is wobbling. He reads out some parts of the text including the phrase ‘depression is setting in,’ followed by a clear sense that he’s reconsidering. Neither of us is left in any doubt,” he wrote.

“I am struck by two things: Boris is genuinely in turmoil, flip-flopping within a matter of hours, and; his cavalier approach.”

The following day, Cameron received a final text from Johnson saying he would be backing Leave – just nine minutes before he publicly announced his intentions in a chaotic press conference outside his London home.

Sir Craig said that Cameron later phoned him to say that Johnson’s final message had been clear that he did not expect to win, believing Brexit would be “crushed”.

“He says Boris is really a ‘confused Inner’, ” he wrote.