President Donald Trump's longtime political ally Roger Stone has after becoming the latest member of Mr Trump's inner circle charged in Special Counsel Robert Mueller's Russia investigation.
In the US federal court in Washington on Tuesday, his lawyer Robert Buschel said Mr Stone pleaded not guilty to the charges of making false statements to congress, obstruction of an official proceeding and witness tampering.
Roger Stone, a longtime adviser to President Donald Trump, gestures as he leaves court. Source: AAP
Mr Stone smiled as he passed through a gauntlet of reporters upon arrival at the courthouse.
A small group of protesters waved Russian flags and a placard that said "Dirty Traitor" while other people showed their support for the 66-year-old veteran Republican operative.
The indictment said Mr Stone told members of Donald Trump's 2016 presidential campaign that he had advance knowledge of plans by the WikiLeaks website to release damaging emails about Trump's Democratic opponent, Hillary Clinton, that US intelligence agencies have concluded were stolen by Russia.
The indictment did not indicate whether Stone knew that Russians had stolen the emails by hacking into computers used by Ms Clinton's senior campaign adviser John Podesta and the Democratic National Committee.
The charges against Mr Stone marked the first time Mr Mueller's team has publicly tied the Trump campaign to WikiLeaks, and raise questions about what Mr Trump may have known prior to the public release of the stolen emails.
The charging documents said a senior campaign official "was directed to contact Stone about any additional releases and what other damaging information" WikiLeaks had about Clinton's campaign but did not disclose the identity of the person who gave the order.
Mr Stone, a self-proclaimed "dirty trickster" and Republican political operative since the days of the Watergate scandal that forced his former boss President Richard Nixon to resign in 1974, was released on a $US250,000 bond after his arrest.
Special counsel Robert Mueller is investigating Russian interference in the 2016 presidential campaign. Source: Getty Images
He has declared his innocence.
In comments to journalists on Monday in Florida ahead of his arraignment, Mr Stone accused Mr Mueller of "a raw abuse of power".
The President has called the investigation a witch hunt and denied any collusion. Russia has denied the US intelligence community's finding that Moscow interfered in the US political arena.
Thirty-four people have been swept up in the Mueller investigation. Those charged include Trump's former campaign chairman and deputy campaign chairman, former national security adviser and his former personal lawyer.
It remains unclear whether any further charges have been filed. Acting US Attorney General Matthew Whitaker on Monday said Mueller's investigation was close to wrapping up and that a report was expected soon.
