Asked about the issue as he travelled to the G20 summit in South Africa, Sir Keir said: “I think the national inquiry can cover this and the approach we’ve taken is no stone unturned.

“Whether it’s in London or elsewhere I’ve always said where there’s evidence that could be investigated by the police, whether that’s looking at old cases or new cases, that should be the first priority because my strong view is in these cases that if there’s evidence to put people before criminal courts that is the first step that should be taken.

“More broadly the national inquiry will leave no stone unturned wherever it is in the country.”

It comes after Sir Sadiq told the London Assembly in June that although the capital has “issues in relation to child sexual exploitation” and “child sexual abuse”, the cases were different from those in other parts of the country.

But last month the Met said it was reviewing 9,000 cases of child sexual exploitation.

It is expected that some of these will be referred to Operation Beaconport, which is looking at cases involving two or more suspects, more than one victim, contact offences, where the suspects are still alive, and which have not already been independently reviewed.

Operation Beaconport is reviewing cases between January 1 2010 and March 31 2025, with thousands expected to come under scrutiny.

Tory London Assembly member Susan Hall said: “It has been 11 months since Sadiq Khan sat there trying to play games with one of the most heinous crimes committed in this country in the last few decades, and only now does he start to treat it as seriously as it is.

“The public should judge Sadiq Khan’s history on this story when they read his comments, and ask themselves why a Mayor who spent months telling us these gangs don’t exist has suddenly had a change of heart.

“It’s a disgrace, it’s paying lip service to the survivors and victims, and it makes me sick to my stomach the way he’s suddenly trying to act like any of his previous comments or actions never happened.”

In January, Ms Hall had pressed Mr Khan during an exchange in City Hall on how many grooming gangs existed in London, but he repeatedly asked her what she meant by the term.

It comes as Sir Keir Starmer caved in to pressure from Tory leader Kemi Badenoch and Reform UK’s Nigel Farage in June when he announced a full national statutory inquiry into grooming gangs.

But the probe was thrown into disarray last month after a group of women quit the victims panel over how the Government had handled the process and called for safeguarding minister Jess Phillips to resign.

However another group of five women came out in support of Ms Phillips and said they would only stay if she remained in post.

Meanwhile, the search for a new chair of the probe is expected to take months after two leading candidates pulled out.

One of the victims Ellie Reynolds said she felt the investigation had become “less about the truth and more about a cover-up”.

She has also called for the resignation of the London Mayor over the issue.

She said last month: “Sadiq Khan’s a liar as well and I think that he should be stepping down.

“I think it was very bizarre of him to try and cover up a mass failing in London as well.”

Met Police chief Sir Mark Rowley said earlier this month that the force will balance its work investigating today’s cases with historical ones which fall within the scope of the national inquiry into grooming gangs.

Sir Mark said he expects reinvestigations of historical cases, which may amount to two to three thousand, will take several years and at least 60 to 80 specialist officers.

He said: “We are determined that, with others, the Met will safeguard victims wherever possible and bring those responsible to justice.”

A spokesperson for the Mayor of London said: “Any individuals or grooming gangs exploiting children for sex are utterly abhorrent and Sadiq wants justice for every single victim of these horrific crimes.

“These children have not only suffered terrible abuse at the hands of the perpetrators but have been woefully let down by the authorities meant to protect them from harm.

“The Mayor has welcomed the Government’s national inquiry and it is right that this should leave no stone unturned when seeking justice for the victims of these horrendous crimes and ensure the vile perpetrators are brought to justice.

“Sadiq has led efforts to strengthen the protection of children from exploitation and harm in all its forms in London, including grooming gangs.

“Since taking office, he has ensured vital investment in specialist services and announced just this week a further £2.4m package of support for victims and survivors of child sexual exploitation.

“He has also driven forward long-overdue reforms in the way the Met protects children. This includes specifically commissioning HMICFRS to independently inspect the Met’s child protection arrangements in 2023, which has led to lasting improvements.

“The Mayor is clear that the Met must follow the evidence wherever it leads, and he will continue to support and hold the Met to account to ensure it does everything possible to tackle child sexual exploitation in London, including grooming gangs.”