New York City will require proof of vaccination to participate in indoor activities, including visiting gyms and restaurants, Mayor Bill de Blasio announced Tuesday.

Why it matters: The mandate is considered to be the first of its kind in the U.S., according to de Blasio. France and Italy announced similar requirements last month.

• Last month, the mayor announced that all city workers would be required to get vaccinated or agree to submit to weekly testing.

State of play: The mandate will move forward beginning the week of Aug. 16 and be fully enforced starting Sept. 13, when schools reopen and people start returning to in-person work.

• New York City will create a health pass called the "Key to NYC Pass" for New Yorkers to provide proof of vaccination for gyms, indoor dining, and live performances and entertainment.

What they're saying: "Not everyone is going to agree with this, I understand that," de Blasio said at a press conference. "But for so many people, this is going to be the life-saving act. That we're putting a mandate in place that is going to guarantee a much higher level of vaccination in this city, and that is the key to protecting people and the key to our recovery."

The big picture: It's the most aggressive move yet to increase vaccinations in New York City. Residents have been able to choose from an array of incentives for getting inoculated, from getting free tickets to city attractions to $100 pre-paid credit cards.

This story is breaking news. Please check back for updates.