Japan's Mitsubishi Motors said Thursday it had been told by a US court to pay $1.01 billion in damages over a 2017 car accident in the United States, adding that it will appeal.

The plaintiff blamed a defective seatbelt design in her husband Francis Amagasu's 1992 Mitsubishi 3000GT that left him with severe injuries after the crash in Pennsylvania.

Amagasu lost control of his car while overtaking and as the vehicle rolled over the seatbelt failed to constrain him properly, according to US media reports.

This caused his head to hit the roof of the car, breaking his neck and leaving him paralysed, the reports said, adding that the damages award was one of Philadelphia's biggest to date.

The court in Philadelphia County on May 6 ordered Mitsubishi Motors to pay $976 million as well as $33 million in delay damages, the Japanese firm said in a statement.

This confirms an earlier ruling by a jury.

"We do not accept the above judgement and MMNA (Mitsubishi Motors North America) plans to appeal to the higher court," Mitsubishi Motors said.

"We will continue to provide vehicles in compliance with applicable laws and safety standards."

In 2022, a US jury ordered Ford to pay damages of $1.7 billion over a 2014 crash in the US state of Georgia that left two people dead.