Washington: President Donald Trump declared himself the victim of the "greatest witch hunt" in American political history and slapped down accusations he tried to quash a probe into collusion between his campaign team and Russia.
Lashing out after a high-powered special counsel was appointed to investigate events around the 2016 election, Trump denied he ever plotted with the Kremlin to win the White House.
"The entire thing has been a witch hunt," Trump said during a press conference in the East Room of the White House.
"There is no collusion between certainly myself and my campaign, but I can always speak for myself, and the Russians -- zero."
An investigation into his campaign's ties with Moscow was significantly strengthened by the appointment of straight-shooting former FBI director Robert Mueller to lead it.
Trump said he had "respect" for the move, but added: "I think it divides the country."
Early in the day, a seething Trump took to Twitter to blast the appointment, which shook Washington and sent world stock markets tumbling.
"This is the single greatest witch hunt of a politician in American history!" Trump wrote, his anger boiling over.
"With all of the illegal acts that took place in the Clinton campaign & Obama Administration, there was never a special counsel appointed!" he said, without providing evidence for those claims.
US intelligence suspects that Russian President Vladimir Putin orchestrated a sweeping campaign to tilt the vote in the Republican's favor.
At the center of the political firestorm are Trump's former national security advisor Michael Flynn and his one-time campaign manager Paul Manafort, and their multiple undisclosed contacts with Russian officials during and after the vote.
So far, no evidence of collusion has been presented, but the question has consumed the first four months of Trump's presidency and spurred multiple crises that have left the White House shell-shocked.