By Patricia Zengerle and Susan Cornwell
WASHINGTON (Reuters) - Former FBI director James Comey accused President Donald Trump on Thursday of firing him to try to undermine its investigation into possible collusion by his campaign team with Russia's alleged efforts to influence the 2016 presidential election.
In the most eagerly anticipated U.S. congressional hearing in years, Comey told lawmakers the Trump administration had lied and defamed him and the Federal Bureau of Investigation after the president dismissed him on May 9.
During more than two hours of testimony, Comey told the Senate Intelligence Committee he believed Trump had directed him in February to drop an FBI probe into the Republican president's former national security adviser Michael Flynn as part of the broader Russia investigation.
Comey would not say whether he thought the president sought to obstruct justice, but added it would be up to special counsel Robert Mueller, who is now investigating the Russia allegations, "to sort that out."
"I don't think it's for me to say whether the conversation I had with the president was an effort to obstruct. I took it as a very disturbing thing, very concerning," Comey testified.
Sitting alone at a small table facing a bank of senators who fired question after question, Comey gave short, deliberative answers. He painted a picture of an overbearing president who he did not trust and who pressured him to stop the FBI Flynn probe.
Trump critics say any efforts by the president to hinder an FBI probe could amount to obstruction of justice. Such an offense potentially could lead to Trump being impeached by Congress, although his fellow Republicans who control the Senate and House of Representatives have shown little appetite for such a move.
Comey did not make major new revelations about any links between Trump or his associates and Russia, an issue that has dogged the president's first months in office and distracted from his policy goals such as overhauling the U.S. healthcare system and making tax cuts.
Nevertheless, the Russia matter likely will continue to overshadow Trump's presidency, especially as the FBI probe has already ensnared not only Flynn but also Trump's son-in-law and adviser Jared Kushner. Attorney General Jeff Sessions has had to recuse himself from the investigation.
After Trump fired Comey, the administration gave differing reasons for his dismissal. Trump later contradicted his own staff and acknowledged on May 11 he fired Comey because of the Russia matter.
Asked why he thought Trump fired him, Comey said he did not know for sure. He added, "Again, I take the president's words. I know I was fired because of something about the way I was conducting the Russia investigation was in some way putting pressure on him, in some way irritating him, and he decided to fire me because of that."
Comey repeatedly said there were details he could not discuss in a public session, making clear he had sensitive information he could disclose only in a closed session with the senators.
'LIES, PLAIN AND SIMPLE'
Comey said Trump's administration had defamed him in comments made after his firing by saying that the FBI was in disarray and that the workforce had lost confidence in its leader. "Those were lies, plain and simple," Comey said.
His accusations could further mire Trump's administration in legal difficulties. Mueller and several congressional committees are investigating what U.S. intelligence agencies have concluded was an effort by Russia to help Trump win the election by discrediting Democratic candidate Hillary Clinton through the hacking and disclosure of damaging emails and other steps.
Russia has denied such interference. The White House as denied any collusion with Moscow.
In a speech to supporters across town, Trump vowed to fight on. "We're under siege ... but we will come out bigger and better and stronger than ever," he said.
"We know how to fight and we will never give up," Trump added.
Trump's personal lawyer, Marc Kasowitz, said Comey's testimony proved the president was not under any investigation and there is no evidence a single vote was changed as a result of Russian interference in last year's election. Kasowitz denied Trump ever told Comey he needed and expected his loyalty, as Comey said.
Comey said he felt he needed to get his account of his conversations with Trump in the public sphere in the hope it might prompt the appointment of a special counsel, which later occurred. Comey said he gave copies of his memo memorializing his talks with Trump to people outside the Justice Department and "asked a friend of mine to share the content of the memo with a reporter."
Comey said he shared the memo with a professor at Columbia Law School, a reference to Daniel Richman, who confirmed to Reuters he was the one Comey referred to in his testimony.
Kasowitz said that "we will leave it the appropriate authorities" to determine whether Comey's leak "should be investigated along with all those others being investigated."
'LORDY, I HOPE THERE ARE TAPES'
Comey said he did not know if there are tapes of his conversations with Trump but said if so they should be made public.
"Lordy, I hope there are tapes," Comey said.
Republicans on the committee questioned Comey intently but did not attack his integrity or try to treat him roughly, as a witness making accusations against a sitting Republican president might expect.
Comey testified he kept notes after meeting with Trump because "I was honestly concerned that he might lie about the nature of our meeting, and so I thought it really important to document."
From Capitol Hill to San Francisco's Castro district, Comey's appearance attracted television "watch parties" beckoning politics buffs to taverns, restaurants and living rooms to view an event some likened to the "Super Bowl of Washington."
U.S. stocks closed slightly higher as the market reacted little to Comey's testimony, viewing his testimony alone as unlikely to mark the end of Trump's presidency.
Comey said Trump did not attempt to get him to drop the overall Russia investigation, just the part of if that related to Flynn, who the president fired in February for misleading Vice President Mike Pence about the extent of his conversations last year with Sergei Kislyak, Russia's ambassador to the United States.
Republican Senator Marco Rubio asked Comey whether he perceived the president's request to let the Flynn matter go as an order given Trump's position as president, the setting and the circumstances surrounding the conversation.
"Yes," Comey replied.
Laura Donohue, a Georgetown University Law Center professor, said if Trump fired Comey to change the course of the Russia investigation, that would constitute obstruction of justice.
Both the conversation between Trump and Comey about Flynn and the firing itself were obstructive acts, she said. "He wanted to scuttle the investigation - it is hard to see it any other way," she said.
Comey's testimony drew new attention to Sessions and his contacts with Kislyak. Comey said he did not discuss Trump's pressure to drop the probe into Flynn with Sessions because the FBI leadership team believed the attorney general would later recuse himself from the Russia probe.
"We were also aware of facts that I can't discuss in an open setting that would make his continued engagement in a Russia-related investigation problematic," Comey said, without giving more details.
Republican Senator Lindsey Graham said he did not believe Trump had committed a crime even if his personal style was often brash, adding, "I'll just say it, if being crude, rude and a bull in a china shop was a crime, Trump would get the death penalty."
