Roger Stone, former campaign adviser to U.S. President Donald Trump, arrives for his criminal trial on charges of lying to Congress, obstructing justice and witness tampering at U.S. District Court in Washington, U.S., November 6, 2019. REUTERS/ Tom Brenner

WASHINGTON (Reuters) - A jury was seated on Wednesday in the trial of President Donald Trump’s adviser Roger Stone, a court official said, setting the stage for opening arguments in a criminal case stemming from former Special Counsel Robert Mueller’s probe of Russian meddling in the 2016 U.S. election.

The 67-year-old veteran Republican political operative - a self-described “dirty trickster” and “agent provocateur” - has pleaded not guilty to charges of obstructing justice, witness tampering and lying to the House of Representatives Intelligence Committee. Stone has been a friend and ally of Trump for some 40 years.