Longtime Donald Trump associate Roger Stone says there is "not one shred of evidence" that he was involved with Russian interference in the 2016 election.
Mr Stone is defending himself in a lengthy statement released ahead of a closed-door appearance before the House intelligence committee on Tuesday.
He has also released a series of supporting documents, including direct messages he exchanged with Guccifer 2.0, the unnamed hacker who has taken credit for breaking into Democratic National Committee email servers.
"While some may label me a dirty trickster, the members of this committee could not point to any tactic that is outside the accepted norms of what political strategists and consultants do today. I do not engage in any illegal activities on behalf of my clients or the causes in which I support," Mr Stone said in the prepared statement.
"There is one 'trick' that is not in my bag and that is treason."
Mr Stone, a Republican strategist who has known Mr Trump for many years and informally advised him during the 2016 campaign, also denies he had advance knowledge of the leak of former Clinton campaign chairman John Podesta's emails and says he never colluded with WikiLeaks founder Julian Assange.
He has long denied that he worked with Russian officials to influence the presidential election.
"I recognise that those who believe that there was collusion between the Trump camp and the Russian state, now say Stone, 'MUST HAVE' been involved, but that is not based on one shred of evidence," Mr Stone writes.
"This is nothing more than conjecture, supposition, projection, allegation, and coincidence, none of it proven by evidence or fact."
Mr Stone's interview comes as the House and Senate intelligence panels are looking into the Russian meddling and possible links to Mr Trump's campaign. Mr Stone has been part of the investigation partly because he has said he communicated during the presidential campaign with Guccifer 2.0.
Mr Stone is, for the first time, releasing those communications, which he says are "innocuous."
The direct messages on Twitter, exchanged over a month-long period, show Mr Stone first congratulating Guccifer for being reinstated on Twitter after he was kicked off, and asking that the account retweet a tweet about how the election could be rigged against Trump. Guccifer writes, "I'm pleased to say that u r great man .... please tell me if I can help u anyhow."
Mr Stone does not respond again until several weeks later, when Guccifer asks him about an article on a Democratic turnout model. Mr Stone replies "pretty standard".
On WikiLeaks, Mr Stone said he was kept apprised of Assange's plans to release the Podesta emails by a journalist he said served as an "intermediary". He did not name the journalist.
Mr Stone has been outspoken in his own defence and asked for his House appearance to be public. But he said the House panel insisted on holding the session behind closed doors.