Former US president Donald Trump on Monday attacked the federal judge overseeing his election conspiracy case, days after the magistrate warned him not to make incendiary statements on the matter.

Using his social network, the former president called US judge Tanya Chutkan "highly partisan" and "very biased and unfair" for previous comments she made in a separate case, in which she oversaw the sentencing of one of the defendants accused in the January 6, 2021 attack on the Capitol.

At a hearing on Friday, Chutkan imposed a protection order in the case, limiting the evidence handed over by prosecutors that the former president and his legal team can disclose publicly.

The magistrate warned Trump's lawyers that his defense should be mounted in court and "not on the internet".

Regardless of the warnings, Trump spoke about the case online and attacked the judge.

Prosecutors requested the protection order after drawing attention to another previous post on Trump's social network, in which he said he would "go after" those who "go after" him.

Prosecutors said that improper sharing of evidence could have a "detrimental effect on witnesses".

Quoted by Lusa, Chutkan said that if anyone made "incendiary" statements about the case, she would be inclined to move more quickly for a trial to avoid any intimidation of witnesses or influence on the jury.

The judge agreed with Trump's defense team on a more flexible version of a protective order that prohibits public disclosure only of materials considered confidential, but prosecutors consider most of the evidence in the case sensitive, so the judge ruled for the government on what will receive that label and protections.

Protective orders are standard in criminal cases to protect the disclosure of confidential information that could affect the trial.

Tanya Chutkan has been one of the toughest judges on the protesters who stormed the US Capitol.

Federal judges in Washington have convicted nearly 600 defendants for their roles in the attack, which was fueled by Trump's unfounded allegations that the 2020 presidential election was won by Joe Biden using fraud.