SNP Westminster deputy Leader Kirsten Oswald called for Mr Johnson to release all correspondence relating to the allegations, including WhatsApp messages and texts, as media reports also claimed the Tory Party paid £58,000 for the renovation of his flat, on top of £30,000 additional expenditure funded by taxpayers.
The total refurbishment may have cost as much as £200,000, with reports a second invoice was paid by a Tory donor directly with the supplier.
Tory donors have also reportedly been approached to pay for Mr Johnson's nanny, personal trainer and personal chef, according to reports in The Sunday Times, which also claimed the Prime Minister has told friends he needs to earn at least £300,000 a year to keep his head above water.
One unidentified Tory MP received a complaint from a supporter who has been asked to pay for childcare for the Prime Minister’s one-year-old son Wilfred.
The donor reportedly told the MP: “I don’t mind paying for leaflets, but I resent being asked to pay to literally wipe the Prime Minister’s baby’s bottom.”
The register of ministerial interests has not been updated since July last year, leaving taxpayers in the dark over Mr Johnson's income and financial interests, in a potential breach of the ministerial code.
Ms Oswald said: "Boris Johnson must be living on another planet if he's whingeing about his dodgy-donor funded luxury lifestyle – when millions of families are struggling to get by as a result of Tory cuts.
"The growing sleaze scandal demonstrates, yet again, that the Tories are only in it for themselves and are completely out of touch with the majority of people across Scotland, who will find Johnson's comments utterly insulting.”
She added: "The Prime Minister must publish his bank statements, all relevant documents and correspondence relating to his dodgy donor flat renovations, and other donation-funded income and expenditure, to ensure full transparency and assist inquiries and criminal investigations.
"If he fails, the stench of sleaze will continue to surround this Tory government – and Johnson could become the first serving Prime Minister to be interviewed under caution by the police and even prosecuted.”
Separate inquiries into how Mr Johnson’s flat redecoration was funded are being carried out by Simon Case, the head of the civil service, Lord Geidt, the independent adviser on ministers’ interests, and the Electoral Commission.
Other reports published this weekend revealed that Conservative Party staff have been given one week to hand over all communication related to renovations of Mr Johnson’s flat or face criminal consequences.
Conservative Party staff received an email from human resources, in the name of Alan Mabbutt, a senior official and registered legal officer, stating: “You are put on notice that this is a criminal investigation.”
Downing Street did not deny a claim the Prime Minister has taken out a personal loan to repay the Conservative Party for the renovations, it has been reported. Such a loan would have to be declared to avoid conflicts of interest.