New York Governor Andrew Cuomo on Friday ordered non-essential businesses to close and banned all gatherings, in an escalation of attempts to contain the deadly coronavirus pandemic.
Cuomo said civil fines would be handed out to anyone violating the order, which he said would come into effect on Sunday evening.
"We're all in quarantine now," he told reporters, adding that New York state was "on pause."
Cuomo's announcement came a day after California governor Gavin Newsom announced a lockdown for the state's 40 million residents.
"They are taking strong steps," President Donald Trump said Friday shortly after Cuomo's press conference.
"I applaud them," Trump added, referring to Cuomo and Newsom.
Cuomo said an executive order would be passed Friday mandating that only essential businesses can remain open from late Sunday.
He essential services included grocery stores and pharmacies.
Cuomo added that "100% of workforces" for non-essential business must stay at home.
Cuomo said that under "Matilda's Law," named after his mother, "non-essential gatherings of individuals of any size" were cancelled.
He ordered residents to only exercise alone and not hold any group activities outside, such as basketball.
He said citizens should avoid public transport "unless urgent and absolutely necessary."
"These actions will cause disruption. They will cause much unhappiness. I understand that," said Cuomo.
The announcement came as the number of confirmed cases in New York hit 7,000.
According to a running tally by Johns Hopkins University, 205 people have died from Covid-19 in the United States, with more than 14,000 people affected.