Volkswagen won’t be meeting a March 24 deadline to outline a diesel fix for U.S. regulators, Automotive News reports.

Volkswagen brand chief Herbert Diess made the admission in a German newspaper on March 5, claiming it will take the embattled company months, not weeks, to work out a fix for vehicles affected by the the diesel emissions scandal.

The company has been having difficulty coming up with a plan to modify hundreds of thousands of diesel vehicles sold in the U.S. in order to meet state and federal guidelines. Any fix to vehicles that left the factory with an emissions-cheating defeat device would have to meet the approval of the Environmental Protection Agency, California Air Resources Board, and U.S. Department of Justice.

Last week, a U.S. District Court judge turned up the heat on Volkswagen by issuing a deadline for the fix — a date that will now have to be ignored.

“I believe we have good chances to achieve an agreement with the authorities in the United States in the next months,” Diess told the Wolfsburger Allgemeine Zeitung.

In January, a lawyer working for Volkswagen said in court that the company was prepared to buy back vehicles that couldn’t be fixed in a timely manner, as well as those that couldn’t be fixed at all.

Older Volkswagen TDI models sold in the U.S. would likely need extensive work performed to bring their emissions up to acceptable levels. Even if a software fix was able to bring the older engines into compliance without greater modifications, owners would suffer a noticeable erosion of performance and fuel economy.

Last October, Volkswagen of America boss Michael Horn told Congress that the bulk of the vehicles impacted by the scandal in the U.S. were older models.

Horn’s statements were the first indication that Volkswagen might be prepared to purchase affected vehicles.