Elon Musk said SpaceX will sue the Federal Aviation Administration for “regulatory overreach” after the agency planned to fine his defense contractor for issues with two launches last year.

Musk’s threat of litigation, in a post on social media platform X on Tuesday, came after the FAA announced it would levy fines amounting to $633,000 against SpaceX because the company had purportedly failed to comply with a variety of licensing and safety-related regulations during those launches.

The FAA said SpaceX used an “unapproved rocket propellant farm” for its EchoStar XXIV Jupiter mission in July 2023. For its launch a month earlier from Cape Canaveral Space Force Station in Florida, SpaceX had modified its communication plans and used a new and unapproved launch control room, the FAA said.

According to a “notice of proposed civil penalty,” the FAA clearly informed SpaceX on June 16, 2023, two days before the launch, that the agency “would not issue a modification” to the SpaceX license. SpaceX went ahead anyway.

Musk and a spokesperson for SpaceX did not immediately respond to CNBC’s request for additional information on the focus of the company’s complaint.

Musk also posted comments on X, characterizing the FAA’s latest proposed civil penalties as “lawfare.”

“NASA puts their faith in @SpaceX for all astronaut transport to and from the [International Space Station], but somehow [FAA] leadership thinks they know better,” he wrote in a post to his almost 200 million followers.

In another post, Musk said, “I am highly confident that discovery will show improper, politically-motivated behavior by the FAA.”

The FAA did not respond to CNBC’s request for comment.

In a recent blog post, SpaceX complained about “difficulties launch companies face in the current regulatory environment,” specifically pertaining to “launch and reentry licensing.”

Last year, the FAA said it would fine the company $175,000 for failure to submit required data ahead of a Falcon 9 launch in 2022. SpaceX had paid that fine in full by last October.

In August, the FAA had to scuttle an approved SpaceX Starship Super Heavy environmental review because Musk’s company failed to disclose that it had received multiple enforcement actions from Texas state and federal environmental authorities.

The FAA’s latest proposed civil penalties highlight the agency’s difficulties obtaining required information from SpaceX in time to review and authorize launches and reentries.

As CNBC previously reported, the federal Environmental Protection Agency and Texas Commission on Environmental Quality found that SpaceX had repeatedly violated the Clean Water Act and failed to obtain proper permits for industrial wastewater discharges at its Starbase facility in Boca Chica, Texas.

In addition to taking on the FAA and environmental regulators, Musk has clashed with the National Labor Relations Board. He filed a federal lawsuit alleging that the NLRB is unconstitutional in its structure, and that its administrative processes violate the concept of the separation of powers.

WATCH: SpaceX will sue FAA