Mayor Bill de Blasio on Tuesday called on Sen. Elizabeth Warren, who dropped out of the 2020 Democratic presidential race last week, to endorse fellow progressive Sen. Bernie Sanders and was ripped for not being focused on combating the coronavirus outbreak in the city.

“I deeply respect @ewarren. Our nation + our party are better + more progressive because of her leadership. Now our progressive movement needs her more than ever,” de Blasio, a Sanders surrogate, wrote in a tweet. “Senator, if the shoe was on the other foot @BernieSanders would have endorsed you already. Please join us!”

Warren withdrew from the race after a poor showing on Super Tuesday, when she came in third in her home state of Massachusetts behind Sanders and former Vice President Joe Biden.

Speaking to reporters outside her Cambridge, Mass., home last Thursday, Warren said she’s in no hurry to say whom she would endorse.

“Let’s take a deep breath and spend a little time on that. We don’t have to decide this minute,” Warren said.

But critics on Twitter questioned why Hizzoner was getting involved in the politics of the Democratic presidential race when there are 36 confirmed coronavirus cases in the city.

Christine Quinn, the former City Council speaker who lost the Democratic primary for mayor to de Blasio in 2013, retweeted Neera Tanden, the president of the Center for American Progress, a liberal think tank in Washington.

“Respectfully, I think a lot of people would think dealing with the coronavirus is a full time job for the Mayor of New York. Maybe stop telling a woman what to do and focus on that,” Tanden said.

Jesse Lehrich, a former foreign policy spokesperson for Hillary Clinton, also pointed out that de Blasio should be concentrating on containing the coronavirus.

“old enough to remember when you spent 6 months trying to get our team to beg for your support in 2016 before endorsing Hillary over Bernie. nobody even cared,” Lehrich posted on Twitter. “don’t you have a public health crisis to deal with?”

Another marveled at de Blasio’s talent for involving himself in lost causes.

“I’m truly impressed at Bill de Blasio’s ability to find new losing battles to insert himself into,” said Tom Gara, the opinion editor at BuzzFeed News.

Biden has picked up the endorsements of six former Democratic presidential rivals.

The former vice president, whose campaign had been foundering, has been on a roll since being endorsed by Rep. James Clyburn, the highest-ranking black lawmaker in Congress, before South Carolina’s primary election Feb. 29.

Biden surged to victory in the Palmetto State and then won 10 of the 14 states voting on Super Tuesday.

Former Democratic presidential candidates Pete Buttigieg, Sen. Amy Klobuchar and former Rep. Beto O’Rourke endorsed Biden on the eve of Super Tuesday.

Former Big Apple Mayor Mike Bloomberg endorsed him after he dropped out of the race last Wednesday.

And Sen. Kamala Harris and Sen. Cory Booker threw their support to Biden over the past couple of days.

Civil rights activist Jesse Jackson endorsed Sanders on Sunday, and the Working Families Party, which had backed Warren’s candidacy, tossed its support to Sanders on Monday.

Sanders faces a critical string of primary races Tuesday when voters in six states — Idaho, Michigan, Mississippi, Missouri, North Dakota and Washington — go to the polls.

Lacking a strong showing, Sanders could find himself far behind Biden, who has 664 delegates to Sanders’ 573.

There are 365 delegates up for grabs Tuesday.