Former US President Donald Trump's chief strategist Steve Bannon has been sentenced to four months in prison for disobeying the US Congress.

He also has to pay a fine of 6,500 US dollars (around 6,645 euros), as US media reported on Friday from the courtroom of a federal court in the capital Washington.

Bannon had ignored a subpoena from the investigative committee into the Jan. 6, 2021 attack on the Capitol and failed to provide requested documents.

The 68-year-old was therefore already found guilty in July, and the sentence was announced on Friday.

The US Department of Justice had demanded six months in prison and a fine of 200,000 US dollars (around 204,000 euros).

Bannon's lawyers, however, had only suggested a sentence of probation and house arrest.

Bannon is reportedly the first person to be sentenced to prison for ignoring a subpoena from Congress in more than 50 years.

He is expected to appeal the verdict.

Bannon had been a central figure in Trump's 2016 presidential campaign.

After Trump's election victory, he then became chief strategist in the White House.

Trump fired him back in August 2017. The two right-wing populists then got closer again.