Peter Navarro, a former Trump trade adviser, has begun serving a four-month prison sentence for contempt of Congress charges.

He surrendered at a federal prison in Miami, after refusing to cooperate with the January 6 committee investigating the Capitol riot.

Navarro was also fined $9,500 for not providing requested documents and testimony about the 2020 presidential election overturn efforts.

His non-compliance was criticized as an attack on the constitutional separation of powers.

Navarro claimed 'absolute testimonial immunity' and executive privilege, which was fact-checked and countered by Fox News host Sandra Smith.

He is the second Trump aide convicted on such charges, following Steve Bannon, who also received a four-month sentence.

The House January 6 committee's final report implicated former President Trump in a 'multi-part conspiracy' related to the Capitol riot.