Trump Wants Congestion Pricing Dead by March 21. Not So Fast, M.T.A. Says.

In the furor and confusion over the Trump administration’s move to kill congestion pricing in New York City, a major question remained unanswered: If the president had his way, when would the tolling program end?

Federal officials, it turned out, had a date in mind: March 21.

The battle over congestion pricing, which the state-run Metropolitan Transportation Authority is counting on to fund billions of dollars in mass transit repairs, is expected to play out in federal court in Manhattan. While many legal experts say that the March deadline is not binding, some question whether President Trump might resort to other tactics, including withholding federal funding for other state projects, to apply pressure.

In a letter last week to New York transportation leaders, Gloria M. Shepherd, the executive director of the Federal Highway Administration, said they “must cease the collection of tolls” by that date. The letter was included in court papers filed on Tuesday in a federal lawsuit brought by the State of New Jersey seeking to stop congestion pricing.

Ms. Shepherd requested that New York leaders work with her agency, which is part of the U.S. Department of Transportation, “to provide the necessary details and updates” regarding the halting of toll operations.

In response, the M.T.A., which operates buses, trains and commuter rail lines in New York and manages the tolling program, vowed to keep collecting the tolls unless a federal judge instructs it otherwise.

“We’re not turning them off,” Janno Lieber, the chief executive and chair of the M.T.A., said at a news conference on Wednesday. “In the meantime, everything is steady as she goes.”