A north-east Conservative MP said he voted against the prime minister “with a heavy heart” following anger from his constituents.
Andrew Bowie, who represents West Aberdeenshire and Kincardine, said he had “not taken the decision lightly”.
But added he had listened to constituents who “remain understandably angry and upset at what has happened”.
The Tory MP made the admission just two hours after saying he would not tell us how he planned to vote, describing it as a “confidential ballot”.
In the earlier interview, he said: “I’m not telling anybody how I’m voting today.
“It’s a confidential ballot and it’s between me and the ballot paper.
“At the minute, I’m not saying anything.”
Asked about his constituents who have taken to social media to ask their MP how he plans to vote, Mr Bowie said: “It’s a confidential ballot paper and I take all of their concerns into account but I’m not going to be saying one way or another.”
‘Utterly appalled’
In a statement issued last week, the Aberdeenshire MP criticised the prime minister and said he was “utterly appalled by the events that were confirmed to have taken place in the Sue Gray report”.
Scottish Tory MP David Mundell took to social media to say he had voted for a “fresh start” and “new leadership for our country”.
After a difficult couple of years and listening to the views of my constituents, I voted tonight for a fresh start and new leadership for our country.
— David Mundell MP (@DavidMundellDCT) June 6, 2022
Fellow MP John Lamont released a late statement on Monday confirming his vote against the prime minister.
He also confirmed his resignation as parliamentary private secretary to Foreign Secretary Liz Truss.
The MP for Berwickshire, Roxburgh and Selkirk said the events in Downing Street were “totally unacceptable” and claimed the government has become “overwhelmed” by them.
He added: “This has been an incredibly difficult decision. I know that many colleagues have been wrestling with their conscience today and I respect that some MPs will have reached a different conclusion.”
Banff and Buchan MP David Duguid sided with the prime minister.
Scottish Conservative leader Douglas Ross decided to vote against the prime minister, saying he has heard “loud and clear the anger”.
It is the fourth position he has taken since the revelations about lockdown parties at Number 10 emerged.
The Moray MP said he “cannot in good faith support Boris Johnson”.
Scottish Secretary Alister Jack backed Mr Johnson.
In a statement released on Monday, he said the prime minister has his “full support”.
The MP added: “He is showing tremendous leadership as we face major challenges at home and abroad.
“I have no doubt that my colleagues in the parliamentary party will vote to show their confidence in the prime minister.”
Mr Johnson pleaded with Tory MPs to back his leadership rather than indulge in “pointless” internal warfare as he faced the crunch vote.
He told Conservatives that “under my leadership” the party had won its biggest electoral victory in 40 years and made a commitment to future tax cuts.
The Conservative party leader also warned them Tory splits risked the “utter disaster” of Sir Keir Starmer’s Labour entering Downing Street, propped up by the SNP.
A handful of Tory MSPs have publicly called for Mr Johnson to be ousted, including senior frontbench spokesman Murdo Fraser.
Mr Johnson was informed early on Sunday afternoon that he would face the vote after more than 15% of the party’s MPs – 54 parliamentarians – submitted formal letters, emails or messages saying they had lost confidence in them.