Watch live: New York City Mayor de Blasio holds a press conference on the coronavirus outbreak

New York City Mayor Bill de Blasio is holding a press conference scheduled at 3:30 p.m. ET to update the public on the coronavirus outbreak, which has infected 328 people across the state as of Thursday afternoon.

Shortly before the press conference, New York Gov. Andrew Cuomo announced a ban on gatherings of 500 or more people across the state "for the foreseeable future" as public officials try to contain the fast moving virus. The ban includes New York City's Broadway theaters, which will need to close starting a 5 pm tonight. Last week, ticket sales on Broadway reached $26.7 million across plays and performances, according to Broadway World.

Earlier in the day, New York's Metropolitan Museum of Art closed its doors starting March 13, including the Met Breuer and the Met Cloisters. Daniel Weiss, the Met's president and chief executive, said the museum is undergoing a rigorous cleaning and further steps will be announced next week.

Globally, there have been more than 127,000 confirmed cases of COVID-19 and at least 4,700 deaths, according to data compiled by Johns Hopkins University. There are at least 1,300 cases and at least 38 deaths in the U.S.

CNBC's Hannah Miller and Sarah Whitten contributed to this report.