Donald Trump associate Roger Stone pleads not guilty to charges in Mueller investigation

Former campaign adviser for President Donald Trump, Roger Stone, arrives at US federal court Credit: Alex Brandon/AP

Roger Stone, a long-time ally of President Trump, has pleaded not guilty to charges in Robert Mueller's Russia investigation.

The political operative appeared for his arraignment at the US federal courthouse in Washington.

He faces charges involving witness tampering, obstruction and false statements about his interactions related to the release by WikiLeaks of hacked emails during Mr Trump’s 2016 presidential campaign.

Protesters outside court in America. Credit: Carolyn Kaster/AP

Stone made no public statements as he arrived for the hearing, he waved to a small crowd of supporters chanting he did nothing wrong and holding up glowing photos of him.

He also largely ignored a group of protesters yelling "Lock him up" and carrying signs reading "dirty traitor".

Stone was arrested early Friday at his Florida home.

He appeared in US federal court in Washington amid new signals about special counsel Robert Mueller probe’s endgame.

Roger Stone arrives at court Credit: Andrew Harnik/AP

Acting Attorney General Matthew Whitaker said on Monday the investigation is "close to being completed", although an exact timetable is unclear.

Mr Mueller’s continued interest in hearing from Stone aide Andrew Miller, who is fighting the grand jury subpoena, indicates the special counsel could be pursuing additional criminal charges against Stone or others related to WikiLeaks’ release of hacked material during the 2016 election.

Stone is the sixth Trump aide charged in Mr Mueller’s investigation.

The long-time ally of President Trump, has pleaded not guilty to charges in Robert Mueller's Russia investigation. Credit: AP

The indictment does not accuse Stone of coordinating with Russia or with WikiLeaks on the release of hacked Democratic emails.

But it does allege he misled politicians about his pursuit of those communications and interest in them.

The anti-secrecy website published emails in the weeks before the 2016 presidential election that the US says were stolen from Democrats by Russian operatives.

Stone, who has alleged without evidence that the FBI used "Gestapo tactics" in arresting him, said he did nothing more than exercise his First Amendment rights to drum up interest with voters about the WikiLeaks disclosures.