JACOB Rees-Mogg has branded Douglas Ross a “lightweight” in a Tory civil war over Boris Johnson’s job.

Speaking to Newsnight, the Tory Leader of the House of Commons doubled-down on his attack on the Moray MP made earlier in the day on LBC.

The friendly fire came after Ross led calls from the Conservatives north of the Border for Johnson to leave office after he admitted attending a BYOB party in the No 10 garden at the height of lockdown.

Ross had a private conservation with Johnson on Wednesday afternoon, of which he refused to disclose the details. However, reports claimed the Prime Minister had been unable to assure Ross that there was no more of the "partygate" scandal yet to come out.

READ MORE: Tory MSPs mount bid to oust Boris Johnson as pressure grows on Alister Jack

The BBC’s Kirsty Wark told Rees-Mogg that all 31 of the Scottish Tory MSPs were now calling for Johnson to step down over the affair.

Rees-Mogg said that Alister Jack, the Scottish Secretary, “who is a big figure is very supportive of the Prime Minister”.

“Douglas Ross has always been quite a lightweight figure.”

The Tory MP then claimed that the BBC was reporting on all 31 Scottish Tory MSPs having called for Johnson to stand down “without them having said this”.

“They need to say this publicly. These sorts of anonymous briefings are not necessarily entirely reliable,” he said.

The Leader of the House of Commons had already launched a broadside at Ross on LBC radio earlier in the day.

Rees-Mogg had said he did not think it was a “surprise” for the Scottish Tory leader to call for Johnson’s resignation.

“He's never been a supporter of the Prime Minister. He has constantly made disobliging comments about the Prime Minister,” Rees-Mogg claimed.

In fact, Ross has been vocal in his support of Johnson. Even after calling for him to step down, he emphasised that he did not regret voting for him to become the UK party’s leader, said he was “proud and privileged” to serve as a minister under him, and praised his efforts through the pandemic, saying that Johnson’s efforts had saved “so many lives”.

However, Rees-Mogg insisted to LBC: "People do sometimes vote for people in leadership elections who don't live up to expectations but I don't think Douglas Ross is a big figure. I think Alister Jack is really serious and senior figure."

Whereas Douglas Ross was, at least in theory, elected by the Scottish Conservatives, Alister Jack was directly appointed to the Scottish Secretary role by Boris Johnson.

The news comes after a comment from Michael Gove also appeared to summarily dismiss concerns about Johnson’s conduct from the Scottish Tories.

Asked about Ross’s call for the Prime Minister to step down, Gove said that Ross was “in Elgin, and the national Tory leader is in London”.

Commenting, SNP Westminster leader Ian Blackford said: “This snide and arrogant remark from Michael Gove, belittling Douglas Ross, underlines the disdain senior Tories hold for Scotland.

READ MORE: Tory MP Michael Fabricant torn apart for absurd defence of Downing Street party

“That they dismiss the views of their own branch office so easily is yet another telling insight into the appalling Westminster attitude to Scotland.”

SNP president Michael Russell added: "Ross and his MSP colleagues now getting to experience at first hand some of the utter disdain and contempt always shown by their London leadership with regard to Scottish views and Scotland.

"Disdain and contempt they previously cheered."

The BBC's Glenn Campbell reported that "it’s not just Jacob Rees-Mogg who’s dissing Douglas Ross".

He said that another UK Government figure had panned the Scottish Tory leader for "wrongly pre-judging" Nicola Sturgeon before the inquiry into her handling of the Alex Salmond case concluded, and suggested that Ross "is doing so again with Boris Johnson before Sue Gray has reported".

In the wake of the comments, BBC Radio Scotland said the Scottish Tories had not made anyone available to appear on their programming this morning.

The civil war comes just a few short months ahead of the 2022 local elections. The Scottish Tories have already sought to make the council vote about unity and the constitution, but their message will be fatally undermined by the friendly fire aimed at their party from its bosses in London.