Cabinet Secretary Simon Case has been urged to launch an independent probe into claims Boris Johnson tried to secure plum jobs for wife Carrie.
Labour called for an investigation, after the Mirror revealed claims this week that Mr Johnson had talked to Downing Street aides about getting jobs for Mrs Johnson.
And it follows allegations he tried to make her his £100,000-a-year chief of staff two years earlier, when he was Foreign Secretary and she was his girlfriend.
Deputy Labour leader Angela Rayner wrote to Mr Case today, saying it was "clearly inappropriate" for the PM to be "judge and jury in his own case."
She suggested either Mr Case, the Cabinet Secretary, investigate the claims himself, refer the matter to a Parliament committee, or encourage the PM to appoint an "emergency interim ethics watchdog" to replace Lord Geidt, who quit last week.
Lord Geidt is reported to believe the incident “could be a matter for his successor” and “could be ripe for investigation”.
Sources told the Mirror the PM wanted to get her a job as a green ambassador in the run-up to the global climate summit in Glasgow. They claim his second idea was to line her up as communications director for the Duke and Duchess of Cambridge’s Earthshot Prize.
The insiders suggest he wanted Mr Simon Case, who had previously been Prince William’s private secretary, to “take soundings”.
But the PM’s closest advisers were said to have vetoed both suggestions, warning either position could undermine his wife’s status as a private citizen.
Mr Case is not believed to have had a conversation about the Earthshot role with the Palace and no formal request was made to COP organisers.
In her letter to Mr Case, Ms Rayner wrote: “Not only does this raise serious questions about sleaze and corruption at the heart of Boris Johnson’s Downing Street, but shows total disregard for taxpayers’ money.
“Indeed, lobbying for a £100,000 taxpayer-funded position for his partner is a shameless act of cronyism, and just another example of this Prime Minister prioritising himself and those close to him over getting value for hard-earned taxpayer’s money.”
Separately, Ms Rayner wrote to Lord Evans, the chair of the Committee on Standards in Public Life, to ask him to instigate a probe, and to express concern at the “glaring hole in the standards system which has been exposed with Lord Geidt’s resignation.”
Replying to Ms Rayner's letter, Mr Case noted he was not Cabinet Secretary in 2018, when Mr Johnson was Foreign Secretary, and that he had "no involvement in any [Foreign Office] staffing matters at that time."
But he confirmed that in autumn 2020, a former member of the No10 team asked him about "opportunities for Mrs Johnson with environmental charities."
He wrote: "I was happy to have an informal conversation with someone involved with the EArthshot prize about what roles were available, as I would have done for anyone with relevant experience who was keen to get involved with charity work."
But he insisted there was "no improper conduct", and would not be referring himself to the Standards Commissioner.
There’s no suggestion that Mrs Johnson was aware of the PM’s alleged conversations.
A No10 spokesman said: “The PM has never recommended Mrs Johnson for a government role or one as part of the Earthshot Prize.”
But they did not deny the claim that he discussed the matter with Downing Street aides.
Pressed on the issue on Monday, the Prime Minister's official spokesman said: "The Prime Minister has never recommended Mrs Johnson for a Government role, or one as part of the Earthshot Prize.
"Beyond that I wouldn't get into any conversations the Prime Minister may or may not have had in private."
