NEW YORK — The de Blasio administration is recommending but not mandating that all residents, regardless of whether they’re vaccinated, wear masks in indoor public spaces. 

Mayor Bill de Blasio and Health Commissioner Dr. Dave Chokshi announced the guidance at a Monday news conference, minutes after Gov. Andrew Cuomo asked cities to adopt new mask rules. 

The new recommendation is based on new data from the Centers for Disease Control and Prevention that suggest that the delta variant of the COVID-19 virus spreads even more quickly than previously thought, Chokshi said. 

“Today, I'm making a strong recommendation that everyone, regardless of vaccination status, wear a mask in public indoor settings,” Chokshi said, stopping short of issuing a mandate. 

The announcement came as de Blasio said that all newly hired city workers must be vaccinated before they begin their jobs, and as he has introduced further rules aimed at pushing vaccination up throughout the city. 

In July, de Blasio mandated that all city employees must either be vaccinated or face required weekly testing for COVID-19 starting in September. That rule went into effect for city health workers on Monday. 

“It’s incentive on the one hand and growing mandates on the other hand,” he said Monday. 

De Blasio also said that he expected further rules to spur vaccination, especially ahead of the reopening of public schools on Sept. 13.

“All options are on the table,” he said. 

In recent days, de Blasio has ramped up efforts to compel and encourage New Yorkers to get vaccinated. The administration is giving out $100 gift certificates to people who get their vaccine at city-run sites; more than 8,300 residents got the gift certificates over the weekend, doubling traffic at the vaccine sites.

De Blasio said that the decision for the city to strongly recommend, but not require, masks in indoor public spaces was “strategic,” because it keeps the emphasis on vaccination and preserves more flexibility for those who are vaccinated. Unvaccinated people are required to wear masks in all indoor and outdoor public spaces. 

Last week, the CDC recommended that vaccinated people who live in areas with high numbers of COVID-19 cases wear masks in indoor spaces. 

“We’re tracking the exact language from the CDC, just as New Jersey and Connecticut have done,” he said. “If you do get vaccinated, and you're around fully vaccinated people, you still have more freedom than folks who are not vaccinated.”

The city is also pushing vaccination among school-age children, with about 200,000 kids aged 12 to 17 who have been vaccinated so far with six weeks left before the beginning of the school year. 

The is launching a $1.3 million ad campaign aimed at encouraging kids to get vaccinated, and is launching vaccine pop-ups at Summer Rising sites, pre-season athletic training and popular back-to-school shopping destinations in every borough. 

Children who receive their first vaccine dose this week will have full immunity by the first day of class, de Blasio noted.