NEW YORK — New York City Mayor Eric Adams, a Democrat, has said for months his city has no more capacity to house asylum-seekers.

On Wednesday, he switched on a virtual ‘No Vacancy’ sign with a dramatic change in policy after absorbing more than 90,000 migrants in the five boroughs since last year with little help from the federal government.

Under a new mayoral directive, single adult migrants will only be allowed to stay in the city’s shelter system for 60 days, after which they will be required to reapply for a slot. The idea, Adams said at a City Hall press conference, is to prioritize shelter beds for families while helping single adults search for other places for them to stay, whether it is with friends or family elsewhere.

“Our goal is: no child, no family is sleeping on the streets,” Adams said. “That’s our goal, and we’re getting closer and closer to being unable to fulfill even that.”

New York City is one of the only metro areas in the country with a right to shelter, meaning people looking for a bed will be housed for as long as they need one. There are about 55,000 migrants in the system, making up slightly more than half of the total shelter population, a record amount.

The Adams administration is challenging the right to shelter law in court. And with Wednesday’s announcement, the mayor laid out a scenario that would have been unthinkable during the last 40 years of the statute’s existence: That someone in need of room and board may be turned away.

While Adams said his goal was not to increase street homelessness, the average shelter stay for a single adult was 509 days during the 2022 fiscal year — nearly 10 times longer than the new 60-day mandate.

As an illustration of the current capacity issues, he pointed to more than 200 migrants who arrived Wednesday. Because there are no beds available, the asylum-seekers must wait — potentially on the streets — until something opens up.

“Right now, we have no space,” Adams said. “So wherever they can wait, they are waiting.”

The city will continue to search for locations to house arriving migrants, and officials have been busing volunteers to other locations throughout the state. But in an effort to communicate the strain on the municipal safety net, Adams is also planning to hand out fliers to asylum-seekers at the border discouraging them from coming to New York City in the first place.

The handbills warn there is no guarantee of shelter and services and caution that the cost of housing, food and transportation are among the highest in the country.

“Please consider another city as you make your decision about where to settle in the U.S.,” the flier, published in English and Spanish, suggested.

The Republican National Committee immediate seized on the policy change, retweeting a copy of the flier with the message: “That’s not very progressive of them!”

New York has become a key political battleground for the immigration debate as Adams has said it cannot afford to be a so-called Sanctuary City without more support from Washington.

The leaflets are a lo-fi substitute for one of Adams’ long-running requests of the federal government to spread out the flow of migrants to cities around the country, rather than allowing them come to New York City en masse.

Throughout Wednesday’s briefing, the mayor and his deputies repeatedly dinged the feds and called on the Washington to expedite work authorization permits for migrants.

Adams did not, however, mention President Joe Biden by name, something that has irked members of the president’s inner circle and endeared him to Republicans.

Wednesday’s announcement was met with skepticism by other New York City Democrats.

“The Mayor’s announcement today doesn’t just undermine the right-to-shelter, but the defining role of New York as a beacon of promise inscribed at the base of the Statue of Liberty,” City Comptroller Brad Lander, a frequent target of the mayor’s ire, said in a statement. “Right to Shelter is the reason that New York City has fewer people sleeping on our streets every night than other major U.S. cities. Limiting the length of shelter stays for asylum seekers will put more people on the streets and strain other city services including hospitals and sanitation.”

 Hajah Bah and Jeff Coltin contributed to this report.