Donald Trump went on the offensive against his former FBI director on Friday accusing him of lying under oath when he testified a day earlier that the President asked him to drop an investigation into a key aide.

Instead he claimed evidence given by James Comey before the Senate a day earlier cleared him of allegations of obstruction of justice and colluding with Russian officials.

“We were very very happy,” he said. “James Comey confirmed a lot of what I said and some of the things that he said just weren’t true.”

He also said he would be happy to give his account of events to a special counsel appointed to head the investigation into Russia links and insisted that he never asked Mr Comey to swear personal loyalty, directly contradicting the former FBI director’s sworn testimony.

“Who would ask a man to pledge allegiance under oath? I hardly know that man," he said.

Mr Trump launched his attack earlier in the day, taunting Mr Comey as a “leaker” on Twitter.

At the same time, Mr Trump’s personal lawyer prepared to file a complaint against Mr Comey over the damning evidence he presented at a Senate hearing a day earlier.

Opponents of Mr Trump were shocked by Mr Comey’s account. He explained how he began taking notes of his White House meetings for fear the President would later lie about their discussions.

He also confirmed that the President asked him to ease of his investigation into Michael Flynn, who was fired as National Security Adviser for lying about the nature of meetings with Russian officials.

But Mr Trump’s team seized on other parts of the evidence, pointing out that Mr Comey said he three times told Mr Trump that he was not under investigation as well as an admission that the former FBI director had passed information to The New York Times about the Flynn conversation.

Marc Kasowitz, Mr Trump’s personal lawyer, was preparing a counterattack yesterday based on that admission and is expected to file a complaint next week with the Justice Department’s inspector general. The watchdog has the power to launch an investigation into Mr Comey’s conduct and whether he broke any rules by passing on notes of private conversations with the President.

James Comey during Thursday's hearing of the Senate intelligence committee credit: AFP

The team is also expected to file a submission with the Senate Judiciary Committee.

The strategy is familiar from Mr Trump’s years as a bullish property developer in New York where he relied on Mr Kasowitz’s legal nous and aggressive litigation to get things done.

However, the complaints could simply add to the number of investigations under way, increasing the sense of a White House overshadowed by questions about the Trump campaign’s ties to Russia.

The issue has proved a difficult distraction ever since US intelligence agencies said they believed the Kremlin ordered a string of cyber attacks to help sway the election in favour of Mr Trump.

Mr Comey’s testimony that the White House tried to thwart his probe was simply the latest twist in a non-stop saga.

Nancy Pelosi credit: AP

Nancy Pelosi, the Democratic leader in the US House of representatives, said his evidence showed Mr Trump’s behaviour was “beyond the pale”.

"There’s no question he abused power," said Ms Pelosi. "Whether he obstructed justice, remains for the facts to come forward, and that’s what we want are the facts."