A Brazilian Supreme Court justice has threatened to detain former President Jair Bolsonaro.

The judge, Alexandre de Moraes, accused Bolsonaro of breaching a ban which bars him from appearing in audios, videos and interviews shared on social media.

Justice Moraes said the ex-president could face "immediate imprisonment" unless his lawyers could provide a satisfactory explanation within 24 hours as to why their client had appeared in a video shared by Bolsonaro's son, Eduardo, on Monday.

Bolsonaro is on trial for allegedly plotting a coup to prevent President Luiz Inácio Lula da Silva from taking office in 2023, which he denies.

Moraes has been leading the investigation into allegations Bolsonaro and his allies committed "antidemocratic acts".

Moraes had already imposed a raft of restrictions on Bolsonaro on Friday, including a night-time and a weekend curfew, as well as 24-hour surveillance, to prevent him from fleeing the country while he is on trial.

Bolsonaro has also been ordered to refrain from contacting foreign governments and their embassies in Brazil.

Furthermore, the ex-president has to wear an electronic ankle tag and is barred from communicating with Eduardo, who has been lobbying on his father's behalf in the United States.

Bolsonaro insists that he has never considered leaving Brazil and called Justice Moraes a "dictator".

The measures were ordered by Moraes following a request from the federal police and with the endorsement of Brazil's Attorney-General's Office.

Police had earlier accused Bolsonaro and his son of trying to obstruct the trial against the ex-president and of violating Brazil's sovereignty by encouraging the US government to interfere in the trial.

On Monday, Moraes gave further details of the restrictions, explaining that Bolsonaro was not just barred from appearing in videos and audios that he himself shared on social media, but also from appearing in those shared or published by third parties.

Shortly after that, Bolsonaro spoke to journalists as he was leaving Congress, where he had met opposition lawmakers.

He showed them his electronic ankle tag, calling it "a symbol of the utmost humiliation".

Footage of the interaction was shared on social media by Eduardo Bolsonaro and supporters of his father, in what Moraes says was a breach of the restrictions he had imposed.

The trial of Jair Bolsonaro, who governed Brazil from January 2019 to December 2022, is being closely followed by US President Donald Trump, who has denounced it as a "witch hunt".

The two men are long-time allies and earlier this month, Trump threatened to slap a 50% tariff on Brazilian goods starting on 1 August.

In his letter to the current Brazilian president, Luiz Inácio Lula da Silva, Trump cited Brazil's treatment of Bolsonaro as a trigger for the tariff hike.

Tension between the two governments rose further on Friday, when - in response to the restrictions imposed on Bolsonaro - the Trump administration revoked the US visa of Moraes and other Supreme Court justices.

President Lula called it an "arbitrary and completely baseless measure" and denounced "the interference of one country in another's justice system".