FedEx CEO and Chairman Frederick Smith said on Tuesday the company's lawsuit against the Department of Commerce is "separate and distinct" from recent shipping incidents involving Chinese technology company Huawei.

The shipping company sued the Department of Commerce on Monday, saying that regulations requiring companies to screen and block packages that could pose a threat to national security violate the company's fifth amendment rights and impose an "impossible burden."

"What really led us to [file the lawsuit] at the end of the day wasn't Huawei at all," Smith said on the company's Q4 earnings call. "It was on last Friday, there were five new entities added with these extraordinarily opaque requirements."

Smith said fines for violations stand at $250,000 per package.

"Contrary to what you hear in the media, we don't have to be complicit in this," Smith said. "It's strict liability. If you make a mistake ... they are empowered under their regulations — not, we think, based on congressional law, but on their own regulation — to fine us or any other common carrier."

FedEx has said the shipping incidents involving Huawei were mistakes. In one incident, FedEx failed to deliver packages shipped from Japan to China, instead sending them to the United States. In another, a package bound to the U.S. from the U.K. containing a Huawei phone was returned to its sender.

Huawei has been at the center of the ongoing trade conflict between China and the U.S., with the Pentagon expressing national security concerns about the Chinese company's products. China launched an investigation into FedEx after the package misdirects.

FedEx reported earnings on Tuesday afternoon, notching $5.01 in adjusted earnings per share on $17.81 billion in revenue for its fiscal fourth quarter. That's above earnings estimates of $4.85 per share and revenue expectations of $17.79 billion, according to Refinitiv consensus estimates.