Along with calling Thune a RINO (a derogatory used by some on the right for “Republicans In Name Only”) in his Twitter message, he also expressed his desire for the state’s GOP governor, Kristi Noem, to run for Thune’s senate seat in 2022.

His tweet from Friday afternoon read: “I hope to see the great Governor of South Dakota@KristiNoem, run against RINO@SenJohnThune, in the upcoming 2022 Primary. She would do a fantastic job in the U.S. Senate, but if not Kristi, others are already lining up. South Dakota wants strong leadership, NOW!”

Trump’s motivation for criticizing Senate Republican Whip Thune on Friday was unclear, but this isn’t the first time the president has voiced his displeasure about him on Twitter. On December 22, the president tweeted: “Republicans in the Senate so quickly forget. Right now they would be down 8 seats without my backing them in the last Election. RINO John Thune, ‘Mitch’s boy’, should just let it play out. South Dakota doesn’t like weakness. He will be primaried in 2022, political career over!!!”

That message appeared to come in response to Thune recently acknowledging President-elect Joe Biden’s victory. On December 21, Thune, while speaking with reporters, remarked that he did not know of any senators who would join House Republicans in challenging Biden’s victory when Congress convenes on January 6 to count certificates of electoral vote.

“The thing they’ve got to remember is, it’s just not going anywhere. I mean, in the Senate it would go down like a shot dog,” he said.

Nearly a week before those comments from Thune, Senator Mitch McConnell recognized Biden’s victory and congratulated President-elect Biden on the Senate floor.

Meanwhile, while South Dakota Governor Kristi Noem has been one of Trump’s most ardent supporters, she responded to Trump’s December 22 tweet by declaring her friendship for Thune. In her own tweet, she also said she would focus on running for reelection of the governorship in 2022.

Thune joins other prominent Republicans the president has publicly lashed out against following the election. After Ohio Governor Mike DeWine referred to Biden as the president-elect, Trump tweeted: “Who will be running for Governor of the Great State of Ohio? Will be hotly contested!” He has also encouraged Congressman Doug Collins to run against Georgia Governor Brian Kemp after the latter certified Biden’s win in his state.

Newsweek contacted Thune and the White House for comment about the president’s tweet, but didn’t hear back at the time of publication.