The construction of Vineyard Wind has employed nearly 4,000 people in Massachusetts, according to the governor’s office.

The other projects targeted on Mondayare Coastal Virginia Offshore Wind, Sunrise Wind and Empire Wind off New York, and Revolution Wind off Rhode Island and Connecticut.

“Nobody has ever seen the executive branch take a hatchet to a particular industry like this executive has with offshore wind,” said Travis Annatoyn, who served as Deputy Solicitor for Energy and Mineral Resources at the US Department of the Interior during the Biden administration. “It’s remarkable, even relative to the administration’s actions on other renewable energy sources.”

Vineyard Wind is nearing the completion of construction, and is currently capable of producing some 572 megawatts of power, according to the governor’s office. The project has been delivering power to the New England grid since the beginning of the year. During a recent cold snap, the project was already eliminating some $2 million a day in costs to ratepayers by displacing the need for additional natural gas.

On Monday, hours after the announcement by the Trump administration, nearly half of the renewable energy on the New England grid was coming from wind, according to ISO-New England’s real time dashboard — largely due to Vineyard Wind.

The decision to pause the lease on a project that is well underway and already delivering power to the grid marks a radical departure from legal precedent, and an escalation of the administration’s effort to thwart the industry.

With this step, some of the region’s most promising clean energy projects — includingone that has previously overcome delays during the first Trump administration as well as lawsuits from wind opponents, in addition to a catastrophic turbine blade collapse last year — are thrown into new turmoil. Monday’s announcement comes just weeks after a federal judge in Massachusetts vacated Trump’s day-one executive order that had blocked wind energy projects.

Like Vineyard Wind, the other projects affected by Monday’s decision had leases that were awarded and had been vetted by the Biden administration.

In making the decision to pause the leases, the Interior Department said unclassified reports from the US government have long found that the movement of massive turbine blades and the highly reflective towers create radar interference called “clutter.” According to the Interior Department, that clutter can obscure legitimate moving targets and generate false targets near the wind the projects.

A 2022 report by the National Academy of Sciences found that the risk of turbines interfering with radars is real, however it determined that it was manageable. And in a December 2024 letter to Revolution Wind developer Ørsted, the Department of Defense found the construction of that project would have no “adverse impacts to DoD missions in the area.”

“There is no statutory authority for a blanket freeze on five leased projects that have already been through extensive analysis including coordination with the Department of Defense on the security issues,” said Patrick Parenteau of the Vermont Law and Graduate School.

Vineyard Wind was halfway complete as of September, with the expectation that it would be complete by the end of the year, with 62 turbines generating enough clean energy to power 400,000 homes in Massachusetts, according to the developer. That’s enough to meet 5.5 percent of the state’s energy demand.

Revolution Wind, meanwhile, would generate enough power for 350,000 homes in Connecticut and Rhode Island. Together, these two projects represent a cornerstone of how the region will transition to clean energy as fossil fuel power plants are retired.

The pausing of the leases puts all of that in question, while raising uncertainties about the state’s ability to meet itsemissions reductions commitments to tackle climate change, as well asthe region’s ability to meet its energy needs.

“These projects are among the biggest sources of new, US electricity generation. They are a big deal,” said Elizabeth Turnbull Henry, president of the Environmental League of Massachusetts. “This administration’s move is illegal, I think the courts will confirm, but it’s also contrary to any pretense of caring about energy affordability, American competitiveness, working people or the rule of law.”

A representative for Vineyard Wind did not immediately respond to a request for comment.

Larry Chretien, executive director of the Green Energy Consumers Alliance, called the decision by the Trump administration “arbitrary, capricious, illegal, and bad energy policy.”

“The playbook is obvious. The feds want to break the finances of these projects and deter developers from even thinking of starting something new,” said Chretien. “And the feds are using our taxpayer dollars to serve the interests of the fossil fuel industries.”

It also comes as a crushing blow to the thousands of workers in Rhode Island and Massachusetts who are employed by the industry, Patrick Crowley, president of the Rhode Island AFL-CIO, said in emailed statement. “The result of these actions remains the same: Workers lose hours, families face uncertainty, and energy prices stay high,” he said.

Antonio Gianfrancesco, a union laborer working on Revolution Wind, said in a statement, “This news just puts extra unneeded financial stress on all of us. We trained for these jobs, we followed every rule, and we’re doing the work right. We just want to keep working.”

Thislatest move against wind projects comes aftermonths of escalating attacks on the wind industry, which had been poised for a major boom prior to Trump coming into office. It is also the first time Trump has stopped a project already delivering power.

Even before taking office, Trump had made clear that he planned to gut the industry, which he has said is expensive and inefficient, while also repeating unproven claims that offshore wind installations kill whales. Trump has also repeatedly called wind turbines “ugly.”

Since taking office, he has issued an executive order to pause leasing and permitting of offshore wind, cancelled funds for wind-related port infrastructure, ordered other projects to stop construction, and directed agencies to find ways to thwart the industry.

For two of the projects targeted on Monday — Revolution Wind and Empire Wind — this is not the first time the Trump administration has halted work.

In August, the administration ordered a work stop at Revolution Wind, thenan 80-percent complete offshore wind development in Rhode Island, citing national security concerns. A federal judge in late September allowed the work to restart pending the government’s review.

Earlier in the year, the administration stopped work at New York’s Empire Wind 1 project, though construction resumed following several meetings between Governor Kathy Hochul and the Trump administration. According to the administration, Hochul had shown a willingness to “move forward on critical pipeline capacity” — an about-face following New York’s past resistance to building new fossil fuel pipelines.

Hochul’s office, however, said that no deals related to a gas pipeline were made.

Vineyard Wind has employed more than 2,800 people — both union and non-union — for various lengths of time, a company official reported in 2024.

Kyle Murray, Massachusetts program director for the advocacy group the Acadia Center, called the decision Monday an unjustified attack by this administration on clean and cheap electricity.

“The end result will be higher energy costs for ratepayers and higher profits for fossil fuel companies and utilities,” he said.

Edward Fitzpatrick of the Globe staff contributed to this report.

Sabrina Shankman can be reached at sabrina.shankman@globe.com.