While House Speaker Nancy Pelosi demanded an immediate briefing on the U.S. airstrike that killed Iranian commander Qassem Soleimani, Republican Sen. Lindsey Graham said Friday that he was informed about the operation beforehand earlier this week while visiting President Donald Trump in Florida.

“I was briefed about the potential operation when I was down in Florida,” Graham, who was spotted Monday playing golf with the president in West Palm Beach, told “Fox and Friends” Friday morning.

“I appreciate being brought into the orbit. I really appreciate President Trump letting the world know you cannot kill an American without impunity,” Graham said. “We’ll stand up for our people. And that is an absolutely essential message.”

Pelosi is a member of the so-called “Gang of Eight” top congressional leaders protocol and the law require be informed of classified intelligence and national security matters, but she and Senate Minority Leader Chuck Schumer were not notified beforehand. An aide to Pelosi told ABC News Defense Secretary Mark Esper did call her afterward Thursday night.

“The night’s airstrike risks provoking further dangerous escalation of violence,” Pelosi said in a statement Thursday night. “America – and the world – cannot afford to have tensions escalate to the point of no return. The Administration has conducted tonight’s strikes in Iraq targeting high-level Iranian military officials and killing Iranian Quds Force Commander Qasem Soleimani without an Authorization for Use of Military Force (AUMF) against Iran. This action was taken without the consultation of the Congress.”

Schumer complained about the lack of consultation on the Senate Floor on Friday.

“The need for advance consultation and transparency with Congress was put in the Constitution for a reason, because the lack of advanced consultation and transparency with Congress can lead to hasty and ill-considered decisions,” he said. “When the security of the nation is at stake, decisions must not be made in a vacuum.”

“This action may well have brought our nation closer to another endless war, exactly the kind of endless war the president promised he would not drag us into,” Schumer added.

The Trump administration’s choice not to inform top congressional leaders continues a pattern that breaks with practices by previous administrations. At the same time, Graham says he also was told about the U.S. mission targeting ISIS leader Abu Bakr al-Baghdadi last October 2019.

GOP Rep. Mark Meadows of North Carolina, who said he had spoken with Trump Friday morning, argued the president couldn’t inform the “Gang of Eight” because of the secrecy of the situation.

“If we’re going to have a major deployment in Iran — which we’re not going to have — then it would be appropriate,” Meadows said on MSNBC, when asked if Trump needed congressional approval.

When Meadows was pressed on whether Trump should have, at least, notified the “Gang of Eight” of the plan as he notified Graham, Meadows continued his defense of the president saying, “You can’t make the decision to take out a key general by committee.”

House Intelligence Committee Chairmam Adam Schiff, D-Calif, also a member of the “Gang of Eight,” echoed Pelosi’s point that the strike was not authorized by Congress.

It’s unclear whether House Minority Leader Kevin McCarthy, R-Calif., was informed of the operation before it was carried out, but he did spend time with Trump this week at Mar-a-Lago and tweeted his support Friday morning.

Graham, a Senate Foreign Relations Committee member as well as chairman of the Senate Judiciary Committee — but not a member of the “Gang of Eight” — also reinforced the administration’s claim that Thursday’s attack was of “preemptive, defensive strike.”

Reactions from other members of Congress ranged from Democrats expressing concern over retaliation to Republicans praising the assassination.

Democratic Sens. Chris Murphy and Richard Blumenthal of Connecticut held a joint press conference in Hartford Friday in which they intended to focus on impeachment, but it was the assassination of Soleimani that dominated their remarks.

“The question we have to ask ourselves today is whether Qasem Soleimani is more dangerous the United States alive – or dead as a martyr,” said Murphy, a Foreign Relations Committee member. “My guess is that the assassination of Soleimani will lead to greater harm to U.S. personnel, U.S. citizens and U.S. interests.”

When asked if they believed the impending impeachment trial could have played a role in the decision to take out Soleimani, Murphy raised the prospect of “ulterior motives.”

“Obviously, with this president you have to worry about ulterior motives. He has made it clear he is willing to use the national security tools at his disposal in order to advance his personal political priorities,” he said. “Iran is constantly planning attacks against USA interests in the region. The question is whether or not it was necessary to assassinate the second most powerful person in the region to stop those attacks”

Blumenthal, who sits on the Armed Services Committee, echoed the concerns of his colleague.

“There is no question, no doubt that Soleimani was a bad actor, an enemy of the United States with American blood on his hands,” he said. “The concern I have now is American security, the safety of Americans in the region and around the world — men and women in uniform, our diplomats and ordinary citizens.”

Meanwhile, Republicans have touted the operation as an unqualified win.

Sen. Marco Rubio, R-Fla., another Senate Foreign Relations Committee member, tweeted at least 20 times Friday explaining his support for Trump’s decision.

“Soleimani is directly responsible for previous & future plans to KILL U.S diplomats & American service members in Iraq & throughout the region. But some are so blinded by hatred of Trump that they argue he has done something sinister. Its crazy. Total derangement,” he said on Twitter.

Iranian officials have warned the U.S. of “vigorous vengeance” and have swiftly moved to appoint a replacement.

ABC News’ Mariam Khan, Trish Turner, Liz Alesse and Sarah Kolinovsky contributed to this report.