Sadiq Khan has been slammed by a policing minister for failing to hold the Metropolitan Police to account.
Policing minister Kit Malthouse said it is necessary that the Mayor of London holds the Metropolitan Police leadership to account for responding to past failures.
Priti Patel wrote to the Met Police in response to the findings of the Daniel Morgan Independent Panel, saying the force was unable to "proactively tackle corruption".
Mr Morgan, a private investigator, was murdered with an axe in a pub in 1987.
She said: "The report paints a very worrying picture of the force and particularly its inability to proactively tackle corruption.
"It is disappointing that there are still shortcomings in the vital processes and procedures necessary to prevent the mistakes made in investigations into Daniel Morgan’s death."
Mr Morgan’s family, who are suing the Met, called for the culture of corruption and cover up that remains rife in the Met” to be confronted.
Mr Morgan’s family called for the culture of corruption and cover up that remains rife in the Met to be confronted. Family handout
They said “unless and until” there are “root-and-branch changes” in its leadership team, “we consider we are unlikely to see any meaningful progress within the Met in relation to police corruption”.
Ms Patel said she was “very disappointed that serious issues still persist”, adding: “Standards must be immediately improved.
“I expect the Mayor of London and the new commissioner to reverse these deficiencies as a matter of urgency.”
Branding the findings “deeply worrying”, Sadiq Khan said: “It is crystal clear to me that action needs to be taken at the highest levels of the Met in order to regain the trust and confidence of Londoners.”
Mr Malthouse told the Commons: “Yesterday, the Home Secretary wrote to the Commissioner of the Metropolitan Police and the Mayor of London to set out her expectation that they respond to her with a clear action plan to remedy these failings.
"I welcome the deputy commissioner’s statement yesterday recognising the need for comprehensive action.
“I put particular emphasis here on the responsibilities of the Mayor of London.
Sadiq Khan Dominic Lipinski
Beyond the statutory responsibility on the mayor to respond to the inspectorate’s report within 56 days, it is incumbent on City Hall to be holding the Met Police leadership to account for responding to past failures.
“This clearly hasn’t happened. And I urge the mayor to work with the Home Office to ensure a new commissioner can address these failings.”
Mr Malthouse added: “This report comes at a time when the Metropolitan Police is under intense scrutiny. I have found myself at the despatch box discussing the force’s culture and standards all too frequently in recent months.
“As someone who over the years worked alongside the Met and (has) seen first-hand the incredible things that that organisation is capable of achieving, I know that there are thousands of officers, staff and volunteers across the organisation who perform their duties with skill, professionalism and pride every day.
"However, when things go wrong, it is vital to acknowledge that fact and take every necessary step to make sure the failings of the past are not repeated.”