Douglas Ross is “likely to be a candidate in the contest” to be leader of the Scottish Conservatives following Jackson Carlaw’s sudden resignation, a fellow party MP backing his bid has said.

After less than six months in the job, Mr Carlaw on Thursday said he made the “painful decision” after realising he is not the best person to lead the party in the run-up to next May’s Holyrood election.

Ruth Davidson stood down from the leadership role in August last year, with Mr Carlaw serving as acting leader until being fully appointed in February.

John Lamont, the Tory MP for Berwickshire, Roxburgh and Selkirk, also confirmed on Friday that Ms Davidson will return to frontline politics and play a part in the team if Mr Ross is elected.

Telling Times Radio he would be campaign manager of Moray MP Mr Ross’s bid to lead the party, Mr Lamont said Ms Davidson “will be taking on Nicola Sturgeon in the Scottish Parliament” up until the election where they hope Mr Ross will swap Westminster for Holyrood.

Ruth will be returning to frontline politics and I think that's a very welcome move

He said: “I think he has not only the skills to unite the Conservative Party in Scotland, but also more importantly the skills to unite the unionists vote within Scotland’s which is currently fragmented between a number of different parties.

“One of the strengths of the SNP is they’re able to consolidate most of the nationalist vote behind them – which clearly poses a threat not just from the Scottish Parliament elections next year but in terms of the possibility or another referendum.

“I was (Ruth’s) campaign manager back in 2011 when she was elected Scottish leader and she has grown from strength to strength since since that point and she’s going to be playing a part and Douglas’s team if Douglas is elected.

“Ruth will be taking on Nicola Sturgeon in the Scottish Parliament between the point of Douglas’s election until next year’s election to the Scottish Parliament when we hope that Douglas is going to be returned as an MSP.

“Ruth will be returning to frontline politics and I think that’s a very welcome move because, as you say, Ruth is a formidable performer and a great advocate for Scotland remaining part of the United Kingdom, which is clearly a very important part of political dynamic in Scotland with opinion polls showing renewed support for nationalists.”

Prime Minister Boris Johnson paid tribute to Mr Carlaw saying he has been a “tremendous servant to the Scottish Conservative Party for more than four decades”.

Michelle Ballantyne, the Tory MSP for the South Scotland region who stood against Mr Carlaw in the leadership contest, said the party “did make a bad choice” in appointing him as leader and she suggested he had been removed in a “stitch up”.

But fellow party MSP Adam Tomkins, who is to quit Holyrood at the 2021 election, told the BBC’s Good Morning Scotland radio programme: “Michelle doesn’t know what she’s talking about.

“The only thing that we need to remember about Michelle is that she was beaten 75/25 in a two-horse race by Jackson Carlaw only a few months ago and I’m afraid that Michelle doesn’t speak for the party.

“I think the reason why we’re worried about the polls is because we think that they might be right for the first time in Scottish history.

“Independence now looks like it might not be the minority pursuit that it’s always been but the position of a majority of Scots and we need to do something about that.

“I think Douglas is exactly that kind of combination of formidable and robust and determined that we do need… I think he will be an outstanding candidate and an outstanding leader if he does announce his candidacy.”

Mr Ross had been a Scotland Office minister but resigned from the role in May over Dominic Cummings’s efforts to defend his trip from London to Durham during the coronavirus lockdown.

He was elected to Westminster in the 2017 general election, taking the seat of then SNP Westminster leader Angus Robertson. He was a regional MSP for the Highlands and Islands in the year prior to that.