Sen. Mike Lee (R-Utah) was one of a few Republican senators to criticize a Pentagon briefing to U.S. senators on Wednesday over the conflict with Iran.

“The worst briefing I’ve seen — at least on a military issue — in my nine years [in the Senate],” Lee told reporters.

During the briefing, Trump said Iran appeared to be “standing down” after the U.S.’s drone strike that killed top general Qassem Soleimani and announced new sanctions against the country. Lee said administration officials told lawmakers not to publicly discuss whether or not to respond to Iran’s military strikes with similar force. The Utah Republican blasted this instruction as “insulting and demeaning” to legislators. Lee also called White House officials’ remarks “unconstitutional” and “un-American.”

“They had to leave after 75 minutes while they’re in the process of telling us that we need to be good little boys and girls and run along and not debate this in public,” Lee said of the group that gave the briefing, which included Secretary of State Mike Pompeo, Defense Secretary Mark Esper and CIA Director Gina Haspel. “I find that absolutely insane.”

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The briefing spurred Lee and Sen. Rand Paul (R-Kentucky) to endorse a resolution introduced by Sen. Tim Kaine (D-Virginia) that forces Trump to end all military action against Iran until he receives approval from Congress, the only exception being if the country issues an immediate threat to the U.S. Democrats are hoping to gain support for the resolution from at least two more GOP senators in order for it to pass.

Sen. Lindsey Graham (R-South Carolina) was one of several Republican lawmakers to praise the White House’s handling of the situation involving Iran.

“A homerun speech by President Trump about the challenges we face with Iran. It was measured and firm,” Graham said.

Many prominent elected officials and media figures have criticized the Trump administration’s decision to escalate the U.S.’s conflict with Iran by drawing comparisons with the lead-up to the Iraq War in 2003, when President George W. Bush‘s administration falsely claimed the country housed weapons of mass destruction.