"DO the right thing and remove this Prime Minister," LibDem leader Alex Cole-Hamilton has urged Scotland's Tory MPs.

The MSP has written to five high-profile MPs urging them to submit letters of no confidence in Boris Johnson.

That's as speculation continues about the number already submitted to the Conservatives' 1922 committee over the unfolding "partygate" scandal.

Douglas Ross, the leader of the Scottish Conservatives, has said "Johnson's position is no longer tenable".

Cole-Hamilton, who lodged a motion in Holyrood on Tuesday calling for Johnson to quit has now put pressure on Tory MPs to send letters to 1922 Committee chair Sir Graham Brady.

Those MPs are Scotland Secretary Alister Jack, his predecessor David Mundell plus Andrew Bowie, David Duguid and John Lamont.

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It states: "I am writing to urge you to submit a letter of no confidence to Sir Graham Brady as chair of the 1922 Committee and publicly call for the Prime Minister to resign his office. Despite everything that has happened, just one Scottish Conservative MP has taken that step.

"The British people have sacrificed a great deal over the course of the past two years with many postponing or cancelling significant life events, care home residents going months without family contact and loved ones dying alone in intensive care units.

"The revelation of sustained rule breaking by the Prime Minister and across Downing Street over the course of two lockdowns has badly eroded public trust and confidence in both the government and in the remaining public health measures."

Cole-Hamilton says he's been "out speaking to people in Conservative-held areas across Scotland" who "know that all the while Number 10 broke the rules and partied".

He goes on: "The country cannot take much more of this. Until there is a general election yours is the only way to remove this Prime Minister. Please take a stand without further delay."

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It'll take a minimum of 54 letters from Tory MPs for Cole-Hamilton to get his wish.

Johnson, who insists he did not know the Downing Street garden party he attended was not a work event, has urged others to wait for civil servant Sue Gray’s report into the events before any action is taken.

It's not known how long that process will take.