British Prime Minister Boris Johnson on Monday backed London's police chief amid outrage about her officers' handling of a high-profile vigil for a murdered woman.

Johnson said he still had full confidence in Metropolitan Police Commissioner Cressida Dick and supported her request for a review into how the force handled the gathering on Saturday.

Dick came under fire after male officers were seen scuffling with the crowd and physically restraining female demonstrators on Saturday.

They had assembled to pay tribute to Sarah Everard, 33, who disappeared on March 3 and whose body was found last week. A Met Police officer has been charged with her kidnap and murder.

"The police do have a very, very difficult job. But there's no question that the scenes that we saw were very distressing," Johnson said.

"The reality is that the country is united still in shock and grief about what happened to Sarah Everard and we must do everything we can to find the answers."

Dick was expected to join Johnson at a meeting of the government's Crime and Justice Taskforce and has resisted mounting calls for her to quit.

She said was "more determined, not less" to remain in her post.

Everard's disappearance and death have ignited  debate across Britain about women's safety in public spaces.

It has also cast a shadow over the government's push to grant the police greater powers to crack down on disruptive protests.

Saturday's event had been banned on coronavirus safety grounds. Police said they moved to act because of public health fears.

The opposition Labour Party, which has condemned policing at the vigil, has said it will vote against the bill on the grounds that it places "disproportionate controls on free expression".

Speaking ahead of a vote on the measures in the UK parliament, Johnson said the bill would bring in "tougher sentences for rapists" and "new measures to tackle domestic violence".

Interior minister Priti Patel has asked the chief inspector of constabulary to conduct a review into the police's handling of the weekend's events.