President Donald Trump lunched at the White House on Thursday with Sens. Mitt Romney, R-Utah, and Susan Collins, R-Maine, among others — breaking bread with a pair of Republicans who could go against him in a Senate impeachment trial.

"He had made some initial comments that related to the impeachment process, but it's nothing that I haven't heard on TV from him," Romney told reporters after the lunch. Prior to the meeting Romney had said he did not plan to "be speaking about the impeachment at all."

Romney also said that his recent back-and-forth with Trump did not come up. When reminded by a reporter that the president recently tweeted "he is a pompous 'ass' who has been fighting me from the beginning," Romney responded, “That's as accurate as it is irrelevant."

"It was a good meeting," Collins told reporters. Asked if she felt Trump was trying to butter her up prior to a potential Senate trial, Collins said, "I didn't get that sense."

Romney and Collins are two of only three Senate Republicans who declined to sign on as co-sponsors to a GOP resolution denouncing the House Democrats' impeachment inquiry, raising questions about how they would vote in a Senate trial to convict and remove Trump from office. The other Republican not to sign on is Sen. Lisa Murkowski of Alaska, another moderate vote who could break from the party.

Collins has said that it would be "inappropriate" for her "to reach conclusions about evidence or to comment on the proceedings in the House" because she will be expected to be essentially a juror once the Senate trial begins.

Romney has been more critical of Trump, tweeting earlier this month: "By all appearances, the President's brazen and unprecedented appeal to China and to Ukraine to investigate Joe Biden is wrong and appalling."

A spokesperson for Murkowski said she would not be attending the lunch "as she is scheduled to be traveling back to Alaska."

Trump has invited a handful of Senate Republicans to the White House for weekly lunches this fall to address a series of policy issues, including impeachment.

In a lunch meeting last week with roughly a half dozen GOP senators, the president passed around a transcript from the first phone call he had with Ukraine President Volodymyr Zelenskiy before it had been released to the public.

"We batted around how long a trial would be and who should testify, but it was all just casual conversation really," Sen. Kevin Cramer, R-N.D., said after last week's lunch meeting.

Republican Sens. James Lankford of Oklahoma, Chuck Grassley of Iowa, John Hoeven of North Dakota, and Rand Paul of Kentucky were also expected to attend the lunch. A source familiar with the meeting told NBC News that no pre-set agenda was shared with invitees.

Thursday's lunch comes while the House Intelligence Committee hears testimony from Fiona Hill, a former White House official, and diplomat David Holmes, in the final scheduled day of public testimony.

Impeachment inquiry: Full coverage

The Senate is unlikely to vote to remove Trump from office, even if a few Republicans such as Collins and Romney defect. The Senate requires a two-thirds majority to convict, or 67 votes. The GOP holds a 53-47 advantage, which would require 20 Republicans to break from the president, assuming that every Democrat votes to convict.

Trump's recent lunch meetings show the White House's desire to highlight how they believe they’re working toward legislative priorities; the president also frequently mentions the importance of party unity, especially as he heads into an election year.