Sen. Mitt Romney (R-Utah) on Sunday, Sept. 22, sided against President Donald Trump on the Biden-Ukraine case, while other congressional Republicans defended the president.

“If the president asked or pressured Ukraine’s president to investigate his political rival, either directly or through his personal attorney, it would be troubling in the extreme,” Romney wrote on Twitter.

Romney’s comments follow the Wall Street Journal report of Saturday, which said a whistleblower argued that the president urged Ukrainian President Volodymyr Zelensky to look into Hunter Biden’s dealings with Ukraine.

The report stated:

‘He told him that he should work with [Mr. Giuliani] on Biden, and that people in Washington wanted to know’ whether allegations were true or not, one of the people said. Mr. Trump didn’t mention a provision of foreign aid to Ukraine on the call, said this person, who didn’t believe Mr. Trump offered the Ukrainian president any quid-pro-quo for his cooperation on an investigation.

But congressional Republicans have defended President Trump by saying that private phone calls between the president and overseas leaders are essential to do his work properly.

“The fact is, the president, to quote John Marshall, is the ‘sole organ’ of U.S. external relations and has to have conversations in confidence with foreign leaders. There’s no practical way to conduct diplomacy without it,” said Rep. Mike Gallagher (R-Wis.).

Meanwhile, Sen. Lindsey Graham (R-S.C.) called for Department of Justice to investigate “all things in Ukraine” and specifically said the “Biden-Ukraine connection” as part of that investigation.

“What relationships if any, did the Biden world have with the Ukraine, what role if any, did Ukraine play in 2016 election. So nobody’s looked at this, but somebody should, so I’m hoping that the Department of Justice will look at the Biden-Ukraine connection like we looked at the Trump-Russia connection,” Graham said.

While speaking to reporters outside the White House on Sunday, President Trump appeared to be willing to release the transcript of the phone call in question.

“We had a very great conversation, very straight, very honest conversation. I hope they can put it out,” he said.