Children ages 2 to 4 years old will need to keep their masks on in New York City schools following a rise in COVID-19 cases, city officials announced.

Mayor Eric Adams previously said the mandate for young children would be lifted April 4, but on Friday he said the mandate will remain for longer due to a rise in cases.

The mayor and the city’s health team said the recent surge is likely due to the new BA.2 subvariant, which is more contagious than the Delta and Omicron variants. They said the rise is being seen in people between the ages of 25 and 34.

Health officials said testing would be key in fighting the new variant. Adams is headed to Washington, D.C. Saturday to ask the government for $15 billion to fund COVID-19 vaccines and testing.

While Adams ended the city's indoor mask and vaccine mandate less than a month ago, he personally recommended that New Yorkers put masks on when they're inside.

A Staten Island judge struck down the mask mandate for children under 5 years old on Friday. Adams said the city is going to appeal the judge's ruling.