Public schools in New York, the US city hardest hit by the coronavirus pandemic, will remain closed until September, Mayor Bill de Blasio announced Saturday.

"There is nothing easy about this decision," the mayor said at a news conference. He added, however, that "it clearly will help us save lives ... It's the right decision."

The death toll in the largest US city has continued to rise -- it now stands at 5,820, according to the latest count from Johns Hopkins University. But the rate of hospitalizations has slowed, authorities say.

De Blasio said he had decided on the step after conferring late Friday with Dr Anthony Fauci, who is leading the government's scientific response to the coronavirus. The city closed its public schools on March 16 as the virus continued its rapid spread.

Families lacking the devices are being loaned city-owned computers or laptops; 175,000 have already been distributed. The closing affects 1.1 million students in what is by far the country's largest public school district.

The school year normally ends in late June, and officials still hope classes can resume in September at the start of the new school year. The mayor praised New York's teachers and parents as "heroes" and said the city would help them as needed.

New York Governor Andrew Cuomo had earlier extended the closing of schools statewide to April 29. The state has registered more than 170,000 cases of the coronavirus, with more than 7,800 deaths. De Blasio also said that 6,000 single adults living in homeless shelters -- one-third of the total -- would be transferred to hotels "to make sure people that need to be isolated are isolated."