Updated

The U.S. Senate advanced a resolution Tuesday that would limit President Donald Trump’s power to conduct war in Iran after Louisiana’s Bill Cassidy, who Saturday, voted in favor of it.

Cassidy had previously voted several times against the resolution. But on Tuesday, he joined Republicans Rand Paul of Kentucky, Susan Collins of Maine and Lisa Murkowski of Alaska, all of whom had previously voted for it.

Tuesday’s vote only clears the way for a full vote in the Senate, and it would then need to pass the Republican-controlled House. Even then, Trump would almost certainly veto it.

But Cassidy’s vote highlights his new willingness to vote against Trump after the president backed a challenger, Rep. Julia Letlow, who ousted him from his seat.

Cassidy on Tuesday also said he would not vote to give $1 billion to fund Trump’s planned

“This is a spit-in-the-eye insult to all my taxpayers in Louisiana, to spend a billion on a ballroom when we should be doing something about the high price of gas, groceries, and healthcare,” Cassidy, R-Baton Rouge, told local reporters in a Tuesday phone press conference.

He also started criticizing Trump’s announcement of a $1.8 billion fund for conservatives who say they were unfairly targeted by former President Joe Biden’s administration.

“I don’t actually see any legal precedent for that. We are a nation of laws, you can’t just make up things whole-piece,” Cassidy told reporters Monday in Capitol hallways.

The Associated Press and staff writer Mark Ballard contributed to this report.