Danish energy company Ørsted said it is taking legal action to challenge the U.S. government’s decision to suspend the offshore wind lease for its Revolution Wind project, a move that threatens a development valued at roughly $5 billion.

The company said it plans to seek an injunction in U.S. court to stop the suspension, which was ordered in late December and affects several offshore wind projects under construction along the U.S. East Coast. The decision was issued by the Trump administration, citing national security concerns.

Revolution Wind, a joint venture owned equally by Ørsted and Skyborn Renewables, is located off the coast of New England and was nearing completion at the time the lease was halted. Ørsted said the project was approximately 87% finished and had been expected to begin generating electricity early next year.

In a statement, Ørsted said the project had moved forward only after extensive regulatory reviews and that billions of dollars had already been spent or contractually committed in reliance on federal approvals.

The legal challenge was filed by Revolution Wind LLC in the U.S. District Court for the District of Columbia. Ørsted and its partner previously disclosed that around $5 billion had already been invested in the project.

The lease suspension was part of a broader action affecting five major offshore wind developments. The announcement triggered sharp declines in offshore wind stocks, with Ørsted’s shares falling 13% in the days following the decision.

The administration said the move followed concerns raised by the U.S. Department of Defense, which warned that offshore wind turbines could interfere with radar systems used to detect and track potential security threats. According to the Interior Department, the size and movement of turbine blades, along with the reflective towers, posed operational risks.

The suspension adds to mounting pressure on offshore wind developers, many of whom have already struggled with rising construction costs, inflation, higher interest rates, supply chain disruptions and regulatory uncertainty. Ørsted last year raised roughly 60 billion Danish crowns, about $9.4 billion, through a discounted share sale to strengthen its balance sheet.

Democratic lawmakers, state officials and industry groups have criticized the lease suspensions, arguing they jeopardize clean energy goals and undermine investor confidence in U.S. offshore wind development.

Ørsted said it is also reviewing options related to Sunrise Wind, another offshore project affected by the government’s decision.