Former Federal Bureau of Investigation Director James Comey’s testimony has been released a day ahead of a highly anticipated Senate hearing, but the event will still be closely scrutinized for Comey’s answers to lawmakers — as well as possible simultaneous comments by President Donald Trump.

Senators will almost certainly ask Comey to explain more details about the loyalty pledge Comey says Trump asked him to give. In his prepared remarks to the Senate Intelligence Committee, Comey — who Trump fired on May 9 — said Trump told him “I need loyalty” when they dined alone in January. But Comey didn’t reply and an “awkward silence followed,” he testified.

Read:Comey’s descriptions of his awkward meetings with Trump read like a novel.

The panel is investigating Russian efforts to interfere in the 2016 presidential elections, and Comey has been expected to face questions about whether Trump pressured him to cancel an investigation into former national security adviser Michael Flynn, whose links to Russia are under scrutiny.

Comey may expand on his testimony, in which he said Trump told him “I hope you can let this go.” Comey says he replied “I did not say I would ‘let this go.’”

Intelligence Chiefs Did Not Feel Pressured on Russia Probe

Comey says in his testimony that he assured Trump he wasn’t personally under investigation.

Read: Trump Today: ‘I wish him luck,’ president says ahead of Comey testimony.

Trump’s firing of Comey rocked official Washington at a time lawmakers and the White House are trying to make progress on both a tax overhaul and health-care reform, two high-profile Republican priorities slowly making their ways through Congress.

Read:Why investors still aren’t freaking out over the Comey firing.

This week, Trump is focusing on plans to invest in U.S. infrastructure, with several events scheduled. The day Comey testifies, Trump is planning to host governors at the White House to discuss the topic.

But a response to Comey from the president is possible, if the past few weeks are an indication. In a tweet on May 12, Trump said Comey had better hope “that there are no ‘tapes’ of our conversations” — a warning against leaking information to the media.

And the president labeled Comey a “showboat” and a “grandstander” during an interview in May with NBC News. Trump has consistently said reports about collusion between Russian officials and his presidential campaign are false, painting the allegations as excuses by Democrats for losing the election.

Also see:Current White House official is target in Russia probe, and Trump told Lavrov that Comey was a ‘nutjob’: reports.

Comey’s testimony comes as the Russia investigation is moving on several different fronts. Former FBI Director Robert Mueller has been named special counsel to oversee the bureau’s probe into ties between Trump associates and Russia. Last week, the House Intelligence Committee issued subpoenas related to the Russia investigation.

Following Comey’s public testimony before the Senate Intelligence Committee on Thursday, he will testify in closed session to the same panel.