California and New York City have reversed an easing of lockdown restrictions after a surge in coronavirus cases ahead of a busy Fourth of July weekend.
Announcing the new plans for California on Wednesday, state governor Gavin Newsom said bars and indoor dining at restaurants would be halted for the next three weeks, while museums, zoos and cinemas would also need to close.
This will be in effect across 19 counties, which make up nearly three-quarters of the state's population, including Los Angeles County.
It comes after California recorded a 50% rise in COVID-19 cases in the last two weeks, with another 43% rise of people being hospitalised with the virus.
"Bottom line is the spread of this virus continues at a rate that is particularly concerning," Newsom said.
"We're seeing parts of the state where we are seeing an increase in not only the total number of positive cases, but a significant increase in the total number of people that are getting tested that are testing positive, meaning the positivity rate, not just the total case rate, is beginning to go up to a degree that obviously generates some concern."
Meanwhile, New York City has backtracked on its decision to resume dining indoors at restaurants next week.
Announcing the plan, Mayor Bill de Blasio and Governor Andrew Cuomo said the decision was made due to concerns of a possible rise of infections as seen in other states.
The former said: "Honestly, even a week ago, honestly, I was hopeful we could. But the news we have gotten from around the country gets worse and worse all the time."
Outdoor dining will be permitted to continue, with De Blasio saying more than 6,000 restaurants had applied for permits to seat customers outside.
He added: "Outdoor dining unquestionably has been a great hit. And I think the bottom line is that outdoors is working, period.
"This is one of the things we’ve learned. Outdoors is where we need to be to the maximum extent possible this summer as we fight back this disease."
The US is, by far, the hardest-hit country by coronavirus, having recorded more than 2.6 million cases and 127,000 deaths.
Hopes for a restriction-free summer for Americans are also now dampening after a number of states were recently forced to press the brakes on their plans to reopen as infections spiked.