NEW YORK (NewsNation Now) — Vaccines will be required for many indoor activities starting Aug. 16 in New York City, marking the first time a city-wide vaccine mandate has been issued in the U.S.

New York City Mayor Bill de Blasio announced the move as part of the city’s initiative to get as many residents vaccinated as possible. He called the new pass “the Key to NYC.”

The new requirement applies to indoor dining, gyms and entertainment venues. The policy, which de Blasio hailed as a first in the nation, will be phased out over the coming weeks and will be enforced starting Sept. 13.

“This is crucial because we know it will encourage a lot more vaccinations,” de Blasio said. “If we’re going to stop the delta variant, the time is now.”

To gain entry to these establishments, New Yorkers will have to either present their paper COVID-19 vaccination card, the state-run Excelsior Pass or the city’s vaccine passport app.

5 million New York City residents, about 66% of adults, are fully vaccinated, according to official data.

“I think he is 100 percent right on that. I mean, we all just have to be… secure. Remember, like a year ago, I was scared to come outside, so vaccination is very important,” Manhattan resident Hayley Weddborn said.

NewsNation spoke with Mohammed Gaber, the president and CEO of GoGetDoc, about vaccine passports. See the full interview in the player below.

The mayor also credited private businesses that have mandated or heavily incentivized vaccines.

“…Dining, fitness, performances, where you see leaders in the private sector already saying clearly, ‘Vaccinations are the answer. We need these strong, clear mandates,'” de Blasio added.

Broadway will require performers, audiences and staff to have vaccination proof. Other business with vaccine mandates include SoulCycle and Equinox, Walmart, Disney, Google, Uber, Morgan Stanley and Tyson Foods.

The restriction is de Blasio’s latest attempt to curb a startling spike in COVID-19 cases linked to the delta variant. De Blasio has focused on getting as many New Yorkers vaccinated as possible while resisting calls to mandate masks indoors, as several cities and counties in California have done.

De Blasio said Monday he was making “a strong recommendation” that everyone wear a mask in public indoor settings but stressed that the city’s “overwhelming strategic thrust” remained getting more people vaccinated.

The mayor announced last week that city employees would be required to get vaccinated by mid-September or to face weekly testing, and he has offered a $100 incentive for city residents who get inoculated.

On Monday, the U.S. reached President Joe Biden’s goal of getting at least one COVID-19 shot into 70% of American adults — a month late and amid a surge by the delta variant that is overwhelming hospitals and prompting renewed pandemic regulations around the country.

COVID-19 cases across the U.S. have increased sixfold over the past month to an average of more than 85,000 per day, a level not seen since mid-February. Deaths have climbed over the past two weeks from an average of 254 per day to 386.