WASHINGTON — A day after Attorney General Jeff Sessions said he would testify this week before the Senate Intelligence Committee, Democratic senators on Sunday urged the panel to question him about the Trump campaign’s ties to Russia in a public hearing, rather than behind closed doors.
It was unclear on Sunday whether the committee planned to question the attorney general on Tuesday in an open or closed session. Either way, senators said he would face pointed questions not only about his contacts with Russian officials, but also about his conversations with James B. Comey, the ousted F.B.I. director.
Members of the Intelligence Committee said they wanted Mr. Sessions to recount what happened during and after the Feb. 14 Oval Office meeting where, according to Mr. Comey, President Trump pressured him to drop the F.B.I. investigation into Michael T. Flynn, the former national security adviser. Mr. Sessions was among those Mr. Trump asked to leave the meeting so he could speak privately with Mr. Comey.
“We’ve had a lot of unnamed sources in the media come out and make statements about Jeff Sessions,” Senator James Lankford of Oklahoma, a Republican who is on the committee, said on CBS’s “Face the Nation.” “It’d be very good to get it directly from him.”
Senator Ron Wyden of Oregon, a Democrat who also sits on that panel, said the American public had the right to hear the attorney general’s answers.
In a letter to the top Republican and Democrat on the committee, Senators Richard M. Burr of North Carolina and Mark Warner of Virginia, Mr. Wyden said: “These matters, which are directly related to threats to our democratic institutions, are of the utmost public interest. I believe we owe the American people transparency.”
Mr. Sessions’s appearance before the committee as it investigates Russian interference in the 2016 election is expected to offer critical details as lawmakers debate whether Mr. Trump’s reported comments to Mr. Comey — that Mr. Trump hoped, in reference to the Flynn investigation, that Mr. Comey could “let this go” — amount to obstruction of justice.
Several Republicans said on Sunday that while Mr. Trump’s request was troubling, it was not criminal.
“If this is trying to interfere in a process of any investigation, it doesn’t seem like it was, No. 1, very effective, and, No. 2, came up more than once in a conversation,” Mr. Lankford said. “So this looks more like an inappropriate conversation than obstruction.”
Senator Susan Collins of Maine, another Republican on the Intelligence Committee, said it was wrong of Mr. Trump to even raise the subject, whether he intended to give an order or not.
“Whether it’s illegal is a whole ’nother issue, and that’s up to the independent counsel,” she said on CNN’s “State of the Union,” referring to Robert S. Mueller III, the special counsel leading the F.B.I. investigation.
Senators are also looking at whether Mr. Sessions violated his recusal from the Justice Department’s Russia investigation by writing a memo recommending Mr. Comey’s firing. Mr. Sessions removed himself from the inquiry after it emerged that he had met at least twice with the Russian ambassador in 2016, though he had testified at his confirmation hearing that he had not had contact with Russians.
Appearing on CBS’s “Face the Nation,” Senator Chuck Schumer of New York, the Democratic leader, said Mr. Sessions would need to answer questions about his recommendation that Mr. Comey be fired in light of Mr. Trump’s admission that his decision was linked to the Russia investigation.
“How does that fit in with his recusal?” Mr. Schumer said. “It doesn’t seem to stand up well to me.”
Mr. Schumer also invited the president to testify before the Senate under oath, as Mr. Trump has said he would do.
If @realDonaldTrump is serious, I’d like to offer him an invitation to testify before the Senate. We would welcome his testimony under oath.
Mr. Sessions had originally been scheduled to testify Tuesday before the House and Senate Appropriations Committees about the Justice Department’s budget. He said he would send in his place Rod J. Rosenstein, the deputy attorney general.
Senator Patrick J. Leahy of Vermont on Sunday criticized Mr. Sessions for canceling his appearance before the Appropriations Committees for a second time. Mr. Leahy is the senior Democrat on the Appropriations Committee, as well as a member of the Senate Judiciary Committee, which oversees the Justice Department.
“You need to testify before both in public,” Mr. Leahy said in a tweet. “You can’t run forever.”
Senators Lindsey Graham of South Carolina and Dianne Feinstein of California, the Republican chairman and the top Democrat on the Senate Judiciary Committee, also called on Mr. Sessions to appear before their committee.
Mr. Graham also called for Loretta Lynch, who served as attorney general during the Obama administration, to appear before the committee, citing Mr. Comey’s testimony to the Intelligence Committee on Thursday that she had asked him to publicly call the investigation into Hillary Clinton’s use of a private email server a “matter” rather than an “investigation.”
“If the attorney general’s office has become a political office, that’s bad for us all,” Mr. Graham said on “Face the Nation.” “So I want to get to the bottom of that, and it should be in Judiciary.”
But Mr. Graham also reserved some criticism for Mr. Trump, who on Sunday morning took his harshest shot yet at Mr. Comey, calling him “very cowardly” in a tweet.
I believe the James Comey leaks will be far more prevalent than anyone ever thought possible. Totally illegal? Very ‘cowardly!’
“You may be the first president in history to go down because you can’t stop inappropriately talking about an investigation that, if you just were quiet, would clear you,” Mr. Graham said.
In an appearance on ABC’s “This Week,” Preet Bharara, the former United States attorney in Manhattan, described what he also called inappropriate actions by the president directed at him, saying that “it appeared to be that he was trying to cultivate some kind of relationship,” similar to Mr. Trump’s behavior that Mr. Comey described last week.
“It’s a very weird and peculiar thing for a one-on-one conversation without the attorney general, without warning, between the president and me or any United States attorney who has been asked to investigate various things and is in a position hypothetically to investigate business interests and associates of the president,” said Mr. Bharara, who was fired by the president hours after he refused to return a call from him.