Washington DC - Former secretary of state Hillary Clinton is due to testify before Congress behind closed doors on Thursday in relation to the scandal surrounding infamous sex criminal Jeffrey Epstein.

Her husband, ex-President Bill Clinton will also be questioned on Friday.

Both will testify via video link, and the sessions are expected to be closed, so it's unclear how much information will be made public.

Hillary and Bill Clinton refused for months to appear before Congress as part of probes into the ongoing Epstein case, risking being held in contempt.

They have accused the Republican chairman of the House oversight committee dealing with the scandal, James Comer, of being politically motivated. Hillary Clinton also accused President Donald Trump's administration of engaging in a cover-up, amid widespread anger at the botched release of millions of Justice Department files related to Epstein.

Bill Clinton's name and photos of him feature heavily in the batches released so far. He has repeatedly denied any wrongdoing in connection with Epstein's crimes.

The notorious financier operated a sex abuse ring for years, victimizing many young women and minors. He died in his prison cell in 2019 awaiting trial on sex trafficking charges.

The revelation of his deep connections to powerful figures from politics, academia, and entertainment has sparked widespread outrage across the political spectrum.