The Metropolitan Police Commissioner has Sadiq Khan's "full confidence", the Mayor's office said on Monday.
Sir Mark Rowley has been under mounting pressure over the policing of pro-Palestine marches and another failure in the Stephen Lawrence murder case.
Mr Khan met the commissioner this afternoon to discuss the issues, which have sparked fresh concerns about the force's leadership.
Sir Mark was also due to meet Home Secretary James Cleverly to discuss an incident where an officer described antisemitism campaigner Gideon Falter as “openly Jewish” when he stopped him crossing the street through a Gaza march.
Mr Falter called for the police chief to resign after the incident.
Following an hour-long meeting at City Hall, a spokesman for the Mayor said: "It was a good, frank and constructive discussion with the Commissioner.
"He has Sadiq’s full confidence in policing London. London is policed by consent and they both agreed getting community relations right is fundamental to that.
“The Commissioner has assured the Mayor that he will continue to drive forward change to ensure the Met does a better job commanding the confidence of all London’s communities and learns the lessons from recent events on how to engage and communicate with them better.
“Sadiq will be unflinching in holding the police to account as the changes that are desperately needed continue to be made. Londoners have his word that he will not rest until they have the police service they deserve – one that is representative, trusted and truly fit for purpose.”
Earlier, the Prime Minister said the Met needs to rebuild the trust of the Jewish community after Mr Falter was threatened with arrest at the pro-Palestine demonstration.
Rishi Sunak said he shared public shock and anger over exchanges between the chief executive of the Campaign Against Antisemitism (CAA), and officers policing the protest in central London on April 13.
But he said he has confidence in Sir Mark if the commissioner works to rebuild the confidence and trust of the Jewish community and the wider public.
The Prime Minister told a Downing Street press conference: "I share the shock and the anger that many are feeling when they saw the clips over the weekend.
"And you know what I would say about Mark Rowley and the police, they do have a difficult job, of course I appreciate that.
"But what happened was clearly wrong. And it's right that they've apologised for that.
"And yes, I do have confidence in him, but that's on the basis that he works to rebuild the confidence and trust of not just the Jewish community, but the wider public, particularly people in London but more broadly.
"And you regain that trust and that confidence by making it clear that the police are not tolerating behaviour that we would all collectively deem unacceptable when we see it because it undermines our values.
"And I think that is critical. And I know the Home Secretary will be meeting the commissioner later today."
