Republican senators clashed with one another and confronted Vice President Pence inside a private luncheon on Thursday, as anger hit a boiling point over the longest government shutdown in history.

“This is your fault,” Sen. Ron Johnson (R-Wis.) told Majority Leader Mitch McConnell (R-Ky.) at one point, according to two Republicans who attended the lunch and witnessed the exchange.

“Are you suggesting I’m enjoying this?” McConnell snapped back, according to the people who attended the lunch.

Johnson spokesman Ben Voelkel confirmed the confrontation. He said Johnson was expressing frustration with the day’s proceedings — votes on dueling plans to reopen the government, both of which failed to advance.

The people who attended the lunch spoke on the condition of anonymity to describe a closed-door session. Aides to McConnell, citing regular policy on GOP lunches, declined to comment on the gathering.

The argument was one of several heated moments in a lunch that came just before the Senate voted on the opposing plans to end the shutdown offered by President Trump and Democrats.

The outbursts highlighted the toll the shutdown has taken on Republican lawmakers, who are dealing with growing concerns from constituents and blame from Democrats, all while facing pressure from conservatives to stand with Trump in his demand for money to build a wall on the border with Mexico.

The votes the Senate cast on Thursday were the first on the shutdown since it began Dec. 22, with McConnell and other GOP lawmakers previously refusing to vote on anything this year unless it had Trump’s approval — a policy that has drawn widespread criticism.

The day ended with some limited signs of progress. After the votes, McConnell and Senate Minority Leader Charles E. Schumer (D-N.Y.) engaged in a face-to-face negotiation that senators hoped would lead to a solution in the near future.

The first proposal, which Trump put forward, would have allocated $5.7 billion for wall funding in exchange for temporary protections for some immigrants. Only one Democrat voted for it. Two Republicans rejected the plan.

One of the Republicans, Sen. Mike Lee (Utah), also spoke out in the lunch. He explained that if Thursday’s votes were merely a party-line exercise, there should be more changes to the nation’s asylum laws, according to one of the people who attended the lunch. Lee also expressed concerns about getting assurances for votes on his amendments.

Six Republicans broke ranks to vote for the Democratic plan, which would have reopened shuttered government agencies through Feb. 8, without any wall money. Among them was Sen. Mitt Romney (R-Utah), who explained in the lunch why he planned to vote for both bills.

Sen. Thom Tillis (R-N.C.), who voted for Trump’s bill but opposed the Democratic plan, started to interrupt him and Romney snapped back, according to one of the people who attended the lunch and another person familiar with it. The exchange was lively but not particularly angry, they said.

Representatives for Romney, Tillis and Lee did not immediately comment.

Senators also voiced their concerns about the shutdown directly with Pence, who was in attendance.

“Nobody was blaming the president,” said Sen. John Cornyn (R-Tex.), speaking about the lunch to reporters afterward. “But there was a lot of frustration expressed about the situation we find ourselves in.”

Also during the lunch, McConnell made clear to Pence and others in the room that the shutdown was not his idea and was not working. According to Republicans familiar with his comments, he quoted a favorite saying that he often uses to express his displeasure with government shutdowns: “There is no education in the second kick of a mule.”

McConnell started using that saying after the 2013 shutdown, which lasted 16 days and ended after the public largely blamed Republicans.

That specific exchange was first reported by the Hill newspaper.