Boston Mayor Marty Walsh announced Monday that the city is rolling back it's economic reopening in an effort to contain the spread of COVID-19, imposing more restrictions than the new limits being required by the state. According to Walsh, other communities following suit include Arlington, Brockton, Lynn, Newton, Somerville and Winthrop.

“We’re going to take action now to reduce in-person activity in our city,” Walsh said. “We’re working to slow the spread of the virus in our city and prevent our hospitals from getting overwhelmed.”

Governor Charlie Baker announced last week that the state would move back to phase III, step 1 of its reopening plan, limiting the size of indoor gatherings and reintroducing some workplace restrictions. Some public-health experts contend that the governor is not acting aggressively or quickly enough. The Boston-area cities are moving back to a modified version of phase II, step 2.

The decision by Boston and other cities to act more aggressively than the state comes as key COVID metrics worsen. Boston said the city's positive test rate for the week ending Dec. 6 was 7.2%, compared to 5.2% the previous week, and that that non-surge ICU beds in Boston hospitals were 90% full at the end of last week.

“If these trends don’t stop, it will be a very difficult winter for our hospitals and for a lot of people” Walsh said during a press conference. “So our public-health experts have been analyzing this data closely and developing a plan. And rather than wait until the situation gets worse, we’re going to be proactive here in the city of Boston and other towns here in Massachusetts.”

Walsh's directive will cap private and public gatherings at 10 people indoors and 25 people outdoors. Certain businesses, including gyms, indoor athletic facilities, movie theaters, performance spaces and aquariums, will be temporarily closed.

Retail stores and hair salons will remain open, and indoor dining will continue under limited parameters. Bar seating in restaurants will be eliminated unless businesses get special approval from the Boston Licensing Board, however — and Walsh urged anyone inclined to dine in to get takeout or delivery instead.

While office spaces can still be filled to 25 percent capacity, Walsh asked employers based in the city to let people work from home if possible.

Walsh stressed that the closures should be taken as part of a broader effort to reduce exposure and risk, rather than an epidemiological indictment of particular activities or settings.

“I want to be clear — this is not about targeting specific sectors that cause the virus,” he said. “This is an effort to … reduce overall activity outside the home using mechanisms afforded by the state’s reopening plan.”

The measures will be reviewed after three weeks and lifted if there’s evidence that COVID-19’s spread has been reduced, Walsh said.

It’s not the first time Boston has acted more aggressively than Massachusetts to contain the pandemic. Walsh mandated mask use in early April, nearly a month before Baker followed suit.