In a court filing, the SEC said the sanctions motion would seek an order to show cause for why Musk should not be held in civil contempt for waiting until just three hours before the scheduled Sept 10 testimony to advise he would not appear.

Musk, whose businesses include electric car maker Tesla and rocket company SpaceX, went to Florida’s Cape Canaveral that day to oversee the launch of SpaceX’s Polaris Dawn mission.

Lawyers for Musk called sanctions “drastic” and unnecessary, saying his testimony has already been rescheduled for Oct 3.

A spokesman for the SEC declined to comment.

The SEC is investigating whether Musk broke federal securities laws in 2022 when he bought stock in Twitter, which he later renamed X.

It sued Musk last October after he refused to attend an interview for the probe. Musk has said the SEC was trying to “harass” him through subpoenas.