Sessions refused to say whether he had ever discussed the Russian Federation investigation with Trump, arguing that he could not disclose private communications with the president.
The committee can hold Sessions in contempt when he doesn't answer questions - but that could elongate the testimony and could potentially take months.
"It is an appalling and detestable lie to suggest I participated in any collusion", Sessions said in his opening statement to members of the committee.
He said he did not recall a third meeting with Russian ambassador to the US Sergey Kislyak in the Mayflower hotel in Washington, despite reports that the Federal Bureau of Investigation had been investigating whether such a contact took place. You say 'This is classified, can't answer it here, I'll answer it in closed session, ' that's bucket number two.
Sessions acknowledged that he had met twice with Kislyak - once during the Republican National Convention and once in his Senate office - and he did not disclose that during his confirmation hearing. "Wyden, there are none", Sessions insisted, his voice rising.
"I'm not able to invoke executive privilege", Sessions said.
Heinrich then noted that there were two ongoing investigations into Russian interference in the 2016 election.
Attorney General Jeff Sessions testifies about the Russian Federation probe at an opening hearing conducted by the Senate Select Committee on Intelligence (SSCI) on Tuesday, June 13, 2017.
At one point, Sen.
"We asked them relevant questions and they basically said "We don't feel like answering" and that's not going to be acceptable (with Sessions)", said Wyden. "We are talking about an attack on our democratic institutions and stonewalling of any kind is unacceptable".
Sessions replied, "I am not stonewalling". I'm following historic policies of Department of Justice.
Comey's decision to announce a year ago that Clinton would not be prosecuted over her emails was a "usurpation" of the Justice Department's authority, Sessions said.More news: Comey's friend says he's turning over Comey's Trump memos to Federal Bureau of Investigation
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Sessions got angry again when Wyden pressed Sessions to explain what facts might be "problematic "about his involvement in the Russian Federation probe, as Comey suggested".
"I didn't meet with them - and now the next thing you know I'm accused of being at some reception plotting some sort of influence campaign for the American election". Wyden. There are none. He added that Mueller will have the "full independence he needs to conduct that investigation" and that there was "no secret plan" to fire him.
Testifying at a packed Senate hearing, Sessions, who was a close Trump adviser during the battle for the presidency, also rejected any idea of misconduct in the ouster of FBI Director James Comey and vowed to defend his honour "against scurrilous and false allegations". The president has denied asking Comey to drop the Flynn matter. "When you're recusing yourself, you are stepping aside, and this sure doesn't look like that", he said.
"It's just like through the looking glass", the attorney general said after thanking Cotton.
"Following a routine morning threat briefing, Mr. Comey spoke to me and my chief of staff". He also said that Comey had later told him he was concerned about the meeting, but he did not say that something improper occurred. On June 5, he tweeted that the Justice Department "should have stayed with the original Travel Ban, not the watered down, politically correct version they submitted" to the Supreme Court.
Attorney General Jeff Sessions on Tuesday avoided answering a handful of questions during his hearing before the Senate intelligence committee - but sought to explicitly avoid saying he is invoking "executive privilege". Sessions said they had decided, even before they were confirmed for their positions at the Justice Department, that they needed to remove Comey because the Federal Bureau of Investigation needed a "fresh start".
Earlier Tuesday, Rosenstein appeared before lawmakers on the Senate Appropriations Committee.
Rumors have recently circulated that the president may seek to sack Robert Mueller, the special counsel appointed to head the high-stakes Russian Federation investigation following Comey's ouster.
Rosenstein said that if the president ordered him to fire the special counsel handling the Russian Federation investigation, he would only comply if the request was "lawful and appropriate".
Rosenstein, who has been on the job for six weeks, said only he could fire Mueller, and only if he found good cause to do so.
House Speaker Paul Ryan, R-Wis., told reporters Tuesday he had confidence in Mueller, and dismissed reports that Trump might fire Mueller as "rumors". Kamala Harris asked whether Sessions himself reviewed the policy before relying on it to refuse to answer questions.
Then, Sessions paused a second, before dialing up his response.