Open this photo in gallery

       Security personnel ask customers for proof of vaccination as they enter City Winery in New York City on June 24, 2021. New York City will soon require proof of COVID-19 vaccinations for anyone who wants to dine indoors at a restaurant, see a performance or go to the gym, Mayor Bill de Blasio announced Tuesday, Aug. 3, making it the first big city in the U.S. to impose such restrictions.

       Frank Franklin II/The Associated Press

       New York City will become the first major U.S. city to require proof of COVID-19 vaccination for customers and staff at restaurants, gyms and other indoor businesses as the country enters a new phase of battling the highly contagious Delta variant.

       The announcement is the latest in a string of initiatives aimed at encouraging more residents to get vaccinated as the Delta variant spreads in the nation’s most populous city.

       “We know this is what’s going to turn the tide,” de Blasio told a news conference.

       About 60% of all New Yorkers have received at least one dose of the COVID-19 vaccine, according to city data. But certain areas, largely poor communities and communities of colour, have lower vaccination rates.

       The policy will be enforced starting Sept. 13. It is similar to measures taken in France to curtail the spread of coronavirus.

       As part of the initiative, the city is creating the “Key to NYC Pass” to provide proof of vaccination to workers and patrons at fitness centres, restaurants and entertainment venues, the mayor said.

       The announcement comes on the heels of several steps taken by city officials to encourage still reluctant residents to get their shots, including a mandate for city employees to get vaccinated or face weekly testing.

       On Monday, New York Governor Andrew Cuomo had urged bars, restaurants and other private businesses to require that customers be vaccinated before they can enter.

       De Blasio, however, has stopped short of mandating face coverings in public indoor settings, saying instead it was strongly recommended.

       The highly contagious Delta variant has been wreaking havoc across the United States, leading to a worrisome increase in infections and hospitalizations.

       Florida and Louisiana were at or near their highest hospitalization numbers of the coronavirus pandemic this week, as one doctor warned of the “darkest days” yet.

       More than 11,300 patients were hospitalized in Florida as of Tuesday, accounting for nearly a quarter of the country’s hospitalized COVID-19 patients, according to data from the U.S. Department of Health and Human Services.

       Louisiana was also dealing with one of the worst outbreaks in the nation, prompting Governor John Bel Edwards, a Democrat, to order residents to wear masks again indoors.

       Florida Governor Ron DeSantis, a Republican, has taken the opposite stance. He issued an executive order last week barring schools from requiring face coverings, saying parents should make that decision for their children.

       Our Morning Update and Evening Update newsletters are written by Globe editors, giving you a concise summary of the day’s most important headlines. Sign up today.