During his own testimony last week, Comey said that he understood Trump's request "to be a directive".
The Senate Intelligence Committee had Comey testify on Thursday, regarding his dismissal, the probe into Russian collusion with the Trump campaign, and Trump's potential obstruction of justice when he possibly directed Comey to downplay the probe into his former national security advisor General Mike Flynn.
Comey said Sessions responded with, essentially, a shrug.
Comey said Thursday that he began documenting his conversations with the president because he had a "gut feeling" Trump might lie about the nature of those meetings.
"I don't think it's for me to say whether the conversation I had with the president was an effort to obstruct", Comey testified. Comey was leading that probe.
In his testimony, Comey said he had asked Sessions not to leave him alone with Trump following meetings where he said Trump had asked Comey for his loyalty. And he can expect questions about his involvement in Comey's May 9 firing, the circumstances surrounding his decision or recuse himself from the FBI's investigation, and whether any of his actions - such as interviewing FBI director candidates or meeting with Trump about Comey - violated his recusal pledge. The reason: Comey testified that he did so to manipulate the situation and force the appointment of a Special Counsel.
Pressure mounted at the start of the week following reports that Sessions offered his resignation to Trump because the President blamed Sessions for exacerbating his Russian Federation problems by recusing himself from the probe. Officials said that Sessions at one point offered to resign as his relationship with the president became increasingly tense.
After Trump had cleared the room, Comey said Chief of Staff "Reince Priebus leaned in through the door by the grandfather clock and I could see a group of people waiting behind him".
Can you commit to discuss with the committee in a closed session the reasons for your recusal from the Russian Federation investigation?
Sessions recused himself from the investigation into Russian interference in the 2016 presidential election because he failed to disclose two meetings with the Russian ambassador during his confirmation hearings. But senators on the committee are expected to question Sessions about his meetings with Russians - a topic that's come under increased scrutiny amid investigations into Russia's interference in the US election.
Spicer told reporters Monday that it "depends on the scope of the questions" and said it was "premature" to say. A spokeswoman for Sessions has denied any such meeting took place.
Attorney General Jeff Sessions' letter on Saturday offering to testify before the Senate intelligence committee on Tuesday caught members of the panel by surprise, and senators are concerned he's trying to avoid testifying publicly, a source familiar with the situation says.