The Health Secretary made the comments after Boris Johnson nominated his father Stanley for a knighthood as part of his resignation honours list.
It was also previously reported that Johnson was looking to name four sitting Conservative MPs for a peerage including Scottish Secretary Alister Jack and Nadine Dorries, who has since announced she will be stepping down as an MP.
During a campaign visit to Lanark on Monday, Yousaf said on the honours system: “It’s corrupt to the core, the honours system, and the House of Lords should be abolished.
“It’s an abomination and an affront to democracy.
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“What I would say very clearly is it’s not only Stanley Johnson of course, it’s Alister Jack who’s been awarded a peerage for being a cheerleader for Boris Johnson while he was partying away while the rest of us were in lockdown.
“So Alister Jack should do the decent thing and resign.”
The Times reported that Johnson’s nominations included up to 100 names and that it was “considerably longer” than that of his predecessors Theresa May and David Cameron with the list currently making its way through Cabinet Office vetting.
A spokesperson for the former PM said: “We don’t comment on honours.”
SNP MP Tommy Sheppard said Johnson was “making a mockery” of the system.
In 2021, senior Tory MP Caroline Nokes and a journalist publicly accused Stanley, a former MEP, of inappropriately touching her at Conservative party conferences.
He denied the incidents, saying he had “no recollection of Caroline Nokes at all”.
The former prime minister has previously faced accusations of cronyism after he nominated his brother Jo Johnson for a peerage in 2020.