The director of the FBI, James Comey, has announced that the bureau is investigating whether members of President Trump’s campaign coordinated with Russia to influence the 2016 election.
Mr Comey’s remarks were made before the House Intelligence Committee on Monday.
“I’ve been authorised by the Department of Justice to confirm that the FBI, as part of our counterintelligence mission, is investigating the Russian government's efforts to interfere in the 2016 presidential election,” Comey said in a prepared opening statement.
“That includes investigating the nature of any links between individuals associated with the Trump campaign and the Russian government, and whether there was any coordination between the campaign and Russia's efforts.”
“This work is very complex and there is no way for me to give you a timetable ...[we’ll] follow the facts wherever they lead.”
Mr Comey added that he would be unable to discuss the exact details of the probe, including which officials in the Trump campaign or administration might be under surveillance.
“Because it is an open, ongoing investigation, and is classified, I cannot say more about what we are doing and whose conduct we are examining,” Mr Comey said. “I can’t go into those details here. I know that is externally frustrating to some folks, but it is the way it has to be.”
WATCH: Mr Comey make the bombshell testimony. Post continues...
Mr Comey went on to dismiss the president’s tweeted claims of a “wiretap” ordered by his predecessor, President Barack Obama, saying: “I have no information that supports those tweets and we have looked carefully inside the FBI.”
He added that the Justice Department also had no evidence.
When questioned as to the process of obtaining a wiretap, Mr Comey explained that "no individual in the United States can direct electronic surveillance of anyone,” only courts are enabled to grant permission for electronic surveillance.
Hours before the bombshell testimony, President Trump took to Twitter - his preferred method of communication - to vent his frustration toward the scrutiny of his campaign’s links with Russia.
“James Clapper and others stated that there is no evidence Potus colluded with Russia,” he tweeted, referencing the former director of national intelligence.
“This story is FAKE NEWS and everyone knows it!”
Donald Trump has previously blamed former president Barack Obama and his “people” for orchestrating protests against him, and for a range of national security leaks.
During a pre-taped interview, President Donald Trump was asked whether he thought his predecessor could have been behind the wave of protests against the new administration, and a series of leaks from the White House to the press - including a call shared with Australian PM Malcolm Turnbull.
“You never know what is exactly happening behind the scenes,” Trump said while speaking to the Fox News morning show Fox & Friends.
WATCH: Trump made the wild claim while appearing on Fox & Friends. Post continues after video...
“I think that President Obama is behind it, because his people are certainly behind it. And some of the leaks possibly come from that group, which are really serious because they are very bad in terms of national security.”
“But I also understand that is politics. In terms of him being behind things, that’s politics, and it will probably continue.”
Unsurprisingly, the 70-year-old president is yet to offer any evidence to backup his claims.