Updated at 2:58 p.m.

Mayor Marty Walsh said Wednesday that despite a surge in coronavirus infections nationwide, Boston has seen infection rates decline slightly for the past several weeks, a hopeful sign that could lead to additional reopening of economic activity.

But for now, Walsh said, he is not ready to kick off ”Part Two” of Phase 3 of reopening, which would include increasing capacity at arts and entertainment venus and indoor businesses like gyms and restaurants.

Walsh also shot down rumors that he has a plan to cancel indoor restaurant dining or take other steps to reduce infections. While plans could change if infection rates rise, as of now, Walsh said he has "no intention" of shutting down restaurants — although he noted that restaurants that have been utilizing public space for outdoor dining will have to stop that service by Dec. 1. Restaurants serving outdoors on private property may continue to do so.

And the mayor expressed cautious optimism at the modest decline over the past three weeks in the city’s positive test rate for COVID-19.

“If we continue in that trend, then there’s no conversation of shutting things down, there’s no conversation about shutting restaurants down,” Walsh said. “We’re actually going to have conversations, probably pretty soon, about bringing people back into schools, things like that. We just need to continue to see that trend.”

Meanwhile Walsh is calling on Congress and the White House to act immediately to pass relief measures, adding that the city and the region could see a spike in individuals and families facing homelessness this winter as state and federal eviction protections expire.

While the city's infection rates have been trending in the right direction, Walsh and other officials are concerned about a possible surge in COVID cases after Thanksgiving as a result of people gathering with friends and family.

The mayor asked people not to use a negative COVID-19 test result as carte blanche to gather with others.

“I know many people want to get tested before Thanksgiving,” Walsh said. “We don't want people to think that a negative test results allows you to have a normal Thanksgiving.”

Those who do attend or host gatherings with guests from outside their immediate households should attempt to serve dinner outdoors if at all possible, or else with windows or doors open to the outside to maximize ventilation. Guests should wear masks indoors, whenever possible, and food should be served by one person who is wearing a mask and gloves, Walsh said.

And Walsh reminded residents that avoiding COVID-19 is about more than their own personal health.

“This really is about older relatives and people with medical conditions and making sure they stay safe. It would be a terrible tragedy to see outbreaks driven by family gatherings,” Walsh said. “We’ve seen what it looks like in hospitals in other parts of the country right now, and we have the power, all of us individually have the power, to prevent this from happening here.”