NEW YORK — Mayor Bill de Blasio on Monday night backed the CDC’s guidance easing mask mandates for people fully vaccinated against COVID-19, but signaled those who work inside city-run buildings will continue wearing face coverings for now.

“It’s the right thing to do at this point,” de Blasio told “Inside City Hall” anchor Errol Louis in his weekly “Mondays with the Mayor” interview.

“The vaccination effort has been extraordinarily successful. We’re pushing back COVID more every day. We’re at a seven-month low for COVID positivity in this city,” the mayor continued. “This is exactly the right time to open up the rules some.”

De Blasio emphasized the CDC is clear about its instructions.

“If you’re vaccinated, you get a lot more freedom,” the mayor said. “And there are still places — schools, hospitals, nursing homes — there are still places where you want to keep the mask on. I think they’re pretty balanced rules.”

But when it comes to municipal workers masking up inside city-run buildings, de Blasio said proceeding with caution is still the best route in the short term, and preached a “go-slow approach indoors, in city offices.”

“Right now, we’re going to be careful in the first weeks of having our city office workers back,” de Blasio said. “We’re going to have a mix of vaccinated and unvaccinated people together by definition, so we’re going to be cautious about that — and certainly interacting with the public.”

But some have voiced concerns that unvaccinated people will forgo face coverings under the guise of being vaccinated. When asked whether the CDC guidance — which in effect depends upon a type of honor system between people — may create misunderstandings on a regular basis or cause another coronavirus outbreak, de Blasio played down the potential issue. 

“That’s not what I’m hearing from our health team. We think this is calibrated to the reality of 7.5 million vaccinations in New York City and climbing, and the fact that the number, the data, is speaking to us,” the mayor said. “The decline in COVID is pronounced and is directly speaking to that massive amount of vaccination.” 

Still, the mayor admitted he thinks millions of vaccinated New Yorkers may still wear their masks “a fair amount of the time,” given their knowledge of the dangers of the virus and how accustomed some New Yorkers are to masking up.