Can Trump legally kill congestion pricing in NYC? We're about to find out.

President Trump’s order to kill the MTA’s congestion pricing tolls sets up a high-stakes legal battle that’s likely to have a lasting effect on transportation in New York.

U.S. Transportation Secretary Sean Duffy sent a letter to Gov. Kathy Hochul on Wednesday stating the Federal Highway Administration revoked its approval of the fees, which since Jan. 5 have charged drivers a $9 daytime toll to enter Manhattan south of 60th Street.

The MTA quickly sued over the order and announced it would continue to collect the tolls until a federal judge tells it to stop. The transit agency is required by state law to use the money from the program to finance $15 billion in mass transit repairs.

“ We're highly confident that this program is going to stand up in court,” MTA Chair Janno Lieber said during a news conference. “Remember, we've been sued in every court east of the Mississippi and we won every time.”

Because some of Manhattan’s streets receive federal subsidies, the MTA needed federal approval to launch the tolls. And in order to get that approval, the MTA spent more than five years working to be admitted to the Federal Highway Administration’s “Value Pricing Pilot Program,” which allows state governments to charge tolls on federally-subsidized roads as a way to ease traffic congestion.

In his letter, Duffy argues congestion pricing doesn’t qualify for the program because it’s a “cordon program” that imposes tolls on much of Manhattan rather than a single highway or bridge crossing. He also argued it “appears driven primarily by the need to raise revenue” for the MTA.

In the lawsuit filed Wednesday, the MTA argued it’s the only party that can “unilaterally decide to discontinue the [congestion pricing] program” under the rules of the federal pilot program.

“In short, FHWA's decision to purportedly terminate the VPPP Agreement is in open disregard of a host of federal statutes and regulations, not to mention the MTA and TBTA's rights under the United States Constitution,” the lawsuit adds.

Eric Goldstein, a lawyer at the Natural Resources Defense Council, which supports congestion pricing, called Duffy’s arguments “dubious.”

“ The courts impose a very high burden when the federal government seeks to reverse course and completely do a 180 turnaround simply because administrations have changed,” Goldstein told Gothamist. “They've got to prove that their rationale is legally justified, and it's hard to see how they can make that case.”

Jack Lester, an attorney who helped lead a now-dismissed federal lawsuit in Manhattan that aimed to stop the tolls, argued the federal government nonetheless holds sway over congestion pricing and has the legal authority to nix the tolls.

“ The federal government has discretion to halt the program,” said Lester. “It’s not a mandatory program.”

Lester’s lawsuit focused on the MTA’s environmental review for congestion pricing, arguing that the agency should have published a more rigorous review than the 4,000-page document it released on the potential effects of the tolls. Now, the MTA is making a similar argument in its lawsuit, asserting that the U.S. DOT must first conduct an environmental review before deciding to nix the tolls.

“This is the definition of arbitrary and capricious — not to mention hypocrisy,” the MTA argued in its lawsuit.

Initial data from the MTA found the tolls have led to a 9% reduction in traffic throughout the tolling zone, agency officials said.

In moving to end congestion pricing, Trump also posted “LONG LIVE THE KING” to his social media accounts.

Hochul on Wednesday said the move not only threatened to defund the MTA — which already spent more than $500 million on equipment to collect the tolls — but also argued it represents federal overreach into a state’s rule-making process.

“ I don't care if you love congestion pricing or hate it,” Hochul said at a news conference. “This is an attack on our sovereign identity, our independence from Washington.”