Mayor Bill de Blasio on Sunday announced that he would seek to close non-essential businesses and all schools, both public and private, in nine ZIP codes in South Brooklyn and Central Queens where coronavirus cases have surged for weeks, as health officials scramble to avert a broader outbreak.

"In Brooklyn and Queens we are having an extraordinary problem, something we haven't seen since the spring," de Blasio said soberly during an impromptu afternoon press conference.

"We have to address this issue forthrightly," he added.

The mayor said the measure, which marks the first significant rollback in the city's reopening, would be subject to approval from the state. He said city officials would be conferring with their state counterparts on Monday. If approved, the closures in these nine ZIP codes would begin on Wednesday.

Under the mayor's proposal, the shutdowns in the nine ZIP codes would remain in effect for at least 14 days until average positivity rates fall below 3% for the last seven consecutive days. However, in a more drastic scenario the city is offering up to the state, the shutdowns could also stay in force for as long as 28 days.

The neighborhoods within the nine ZIP codes are as follows: Borough Park (11219), Gravesend (11223), Midwood (11230), Bensonhurst (11204), Flatlands (11210), Gerritsen Beach/Homecrest/Sheepshead Bay (11229) in Brooklyn; and Far Rockaway (11691), Kew Gardens (11415), Kew Gardens Hills (11367) in Queens.

More than 500,000 residents reside in these communities, many of them with a significant Orthodox population. Health officials have targeted their outreach efforts to Orthodox residents by making robocalls and broadcasting announcements in Yiddish as well as speaking to religious and community leaders.

Houses of worship in these nine ZIP codes would remain open during the temporary shutdown, though only "individual worship" will be permitted, his spokesperson Avery Cohen said.

Average positive COVID testing rates over the last two weeks in these areas have been above 3%, a level that health officials consider to be a warning threshold. In Gravesend, the positivity has soared to nearly 7.6%.

Citywide, the average seven-day positivity has been creeping upward from around 1% during most of the summer to now 1.72%.

The proposed shutdowns would occur for at least seven consecutive days until the positivity rates improve, de Blasio said.

The news comes after New York City achieved a milestone of being the only major city to reopen schools for indoor instruction. Worried about the surging infections, the city’s teachers’ union had pressed the mayor last week to close schools in the affected neighborhoods. The mayor said the nine ZIP codes are home to 100 public schools and 200 non-public or private schools.

City Councilmember Mark Treyger, who chairs the education committee and represents parts of South Brooklyn, including Gravesend, immediately criticized the mayor, saying that it did not make sense for children to continue to attend schools in those neighborhoods until Wednesday.

"It speaks volumes that we have massive amounts of confusion in the city, when in a pandemic, you need crystal clear clarity," Treyger told Gothamist/WNYC. "It doesn't cost a dime for the mayor to be honest and transparent with New Yorkers."

"You're telling the public it’s not safe to go to school in these ZIP codes, but you’re telling families send your kids to school one day this week, in those ZIP codes?" Treyger added. "I don't think this will be sustainable. I do believe that we need to move toward a system-wide responsible shutdown to go remote."

A Borough Park teacher at P.S. 164, Julia Dimant, felt "cautiously optimistic" about the ZIP code-based shutdown.

"Quite frankly, I think it's the right plan," Dimant said. The extra two days before implementation on Wednesday—pending state approval—will "give educators an opportunity to go into the building to really prepare and make sure that starting that Wednesday, we'll be able to be fully ready to go remote for our students."

Southeast Queens Councilmember Donovan Richards said the de Blasio administration must do better to engage with community leaders and community-based organizations on such plans.

"If they're not a part of this plan, then this plan is bound to fail," Richards said. "How are we truly working with communities rather than just sending sound trucks through blocks? You gotta get to people who they trust."

In addition to the nine ZIP codes, the city is also monitoring 11 other ZIP codes where infections have also been climbing at an alarming rate. The mayor said that the city is additionally proposing to close indoor dining, gyms and indoor pools—activities deemed high-risk for virus transmission—in those 11 ZIP codes starting on Wednesday until further notice.

Shortly before de Blasio's briefing, Governor Andrew Cuomo announced he would roll out a state task force to enforce coronavirus rules in the hotspot ZIP codes across Brooklyn, Queens, and Rockland and Orange counties.

Throughout the crisis, Cuomo and de Blasio have clashed over New York City's coronavirus response, from school closures to social distancing enforcement of bars and restaurants.

Last week, Cuomo castigated local governments for failing to enforce the state's public health rules, opting instead to focus too much on public awareness campaigns.

Last week, the city distributed 800,000 face masks. Overall, 2,000 inspections have been conducted to date, resulting in 26 violations and 883 warnings. Since Tuesday, health officials have ordered at least five yeshivas to close.

When asked about coordination and why the city would announce details before they're official, de Blasio said: "I think the bottom line is that we want the state to know in a very public manner what we believe will allow us to contain the situation in these nine ZIP codes and protect the 11 ZIP codes that are on this watchlist."

Cuomo's spokesperson, Rich Azzopardi, referred to the governor's earlier statements.

"Local governments have not done an effective job of enforcement in these hot spot ZIP codes," Cuomo said during a Sunday press call.

In a statement, Cuomo said the state would close business activity in areas where local governments "cannot or will not perforce effective enforcement."

"If the localities do not do testing immediately in the schools in those areas, the State will close them immediately," Cuomo added.

With reporting contributed by WNYC's Mirela Iverac.