THE SNP have challenged Rishi Sunak to “undertake a deep clean” of his Conservative government as damaging revelations grow over the behaviour of Tory ministers.

In a letter written by SNP Westminster leader Stephen Flynn, he called on the Prime Minister to sack Nadhim Zahawi as well as remove the whip from Boris Johnson.

This comes following reports that Zahawi, who currently serves as minister without portfolio, admitted he paid a tax settlement after HM Revenue & Customs disagreed with the allocation of founder shares his father took when he set up YouGov.

He has said that all his tax affairs “were up to date” when Sunak appointed him Tory party chairman.

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Meanwhile, it was reported in The Sunday Times that Johnson was assisted by the now chairman of the BBC Richard Sharp to secure a loan of £800,000.

Flynn warned these matters are now a question of the Prime Minister’s own integrity.

He said: “With every day that passes, more damaging revelations are exposed about the sleaze, cronyism and corruption at the rotten core of this Tory government.

“The growing stench of sleaze shows exactly why Scotland needs independence to escape Westminster control.

“Rishi Sunak must undertake a deep clean of the Conservative Party – sacking Nadhim Zahawi, withdrawing the whip from Boris Johnson, and establishing an independent inquiry, if he wants to restore any of the public trust he has lost.”

In the letter to Sunak, Flynn reminded Sunak of his promise to lead a government based on “integrity, professionalism and accountability”.

“Less than 3 months later, that promise lies in complete tatters”, the letter reads.

The SNP Westminster leader also called for the UK Government to establish an independent inquiry into the actions of the former prime minister and chancellor.

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The Labour Party have already reported Johnson to the Parliamentary Commissioner for Standards.

Flynn continued: “This is now a question of Rishi Sunak’s own integrity. If the Prime Minister fails to act, he will breach the commitment he gave to lead a government with ‘integrity, professionalism and accountability’ – and allegations of sleaze and corruption will haunt the Tory government until voters can boot them out at the next election.

“People rightly think this Tory government is only out for itself – and Tory ministers are more focused on lining their own pockets than tackling the issues that matter to families.

“With the pro-Brexit Labour Party joining the Tories on so many issues, only independence can rid Scotland of the broken Westminster system and deliver the change we need.”

In his letter, Flynn also slammed the “ignorance” of Foreign Secretary James Cleverly, saying he “couldn’t answer the most basic questions on all of these scandals”.

Cleverly insisted that Zahawi’s tax affairs are “private matters” and denied that he had any more knowledge of the situation than what had already been said in the former chancellor’s statement.

When asked about reports surrounding Johnson and Sharp, he said that the BBC chair was appointed on merit.

A BBC spokesman said that the broadcaster plays “no role in the recruitment of the chair and any questions are a matter for the Government”.

Downing Street has been approached for comment on Flynn’s letter to Sunak.