Scottish Conservative MP Andrew Bowie resigned from his position as vice-chair of the party, claiming his priorities lie in his north-east constituency.
His announcement comes following a week of accusations the Tory party was embroiled in “sleaze”.
Mr Bowie decided to “step back” from the part-time paid position to spend more time in West Aberdeenshire and Kincardine – and pledged to secure the future of Scotland’s place in the UK.
Prime Minister Boris Johnson is meanwhile having to deal with the reporting of “cash for honours” allegations to the Met Police.
He is also facing a furious public and political backlash to the ongoing row over MP lobbying in the Owen Paterson scandal.
Lobbying row
Mr Bowie voted in favour with other Scottish Tory MPs to help Mr Paterson avoid suspension despite finding he was guilty of paid lobbying, which is against the rules.
Mr Paterson then resigned, and Mr Bowie is reportedly unhappy with how the situation has been handled by the party.
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In a statement, Mr Bowie said he would continue in the position until a replacement is found.
“I was honoured to serve as vice-chair of the Conservative and Unionist Party,” he said.
“However, over the last few months, I have come to the decision that I need to take a step back from the demands of the role to focus on representing my constituents in West Aberdeenshire and Kincardine.
“I formally asked the party yesterday if I could step back from my position and I will remain in post until they have found a successor.”
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The vice chair position comes with a “part time” salary, according to the register of members’ financial interests.
Mr Bowie has been in the role since October 2019, just before Prime Minister Boris Johnson called the snap winter election.
He was elected in 2017, in the 2017 election amid the Brexit fallout and was the first Scottish Conservative MP of that intake to be given a government role, after being appointed to the position of parliamentary private secretary (PPS) within the Department for Digital, Culture, Media and Sport (DCMS).
Later in 2018 he was promoted to PPS for then-prime minister Theresa May, serving in the position until she resigned in July 2019.
Mr Bowie has a slim majority of 843, having had a close contest with the SNP candidate Fergus Mutch.
‘In a huff’
An SNP spokesperson said: “If Andrew Bowie quitting his party position is not about the indefensible behaviour of his Government, then his decision is clearly not about integrity.
“After voting with the Government to save Owen Paterson’s skin, he has no integrity to defend.”
The spokesperson highlighted Mr Bowie’s campaigning visit to Kent this week, also questioning whey the party would focus on the union if it is set against another referendum.
“Maybe he has simply gone in the huff because he was again overlooked as a Scotland Office Minister in favour of an unelected lord,” the SNP spokesperson said.
Asked to respond to political opponents’ attacks on his motives for quitting, Mr Bowie added: “At heart I have been a constituency MP since 2017 and that’s where my priorities lie.
“I’ve really enjoyed my time as VC and will continue to do so until someone else is appointed. The highlight has been meeting so many young and passionate people who will be the next generation of Conservative politicians.”