US President Donald Trump ordered a strike on three of Iran's nuclear sites at midnight on Saturday, a move that has caused mixed reactions among US politicians — from support to calls for impeachment.

Congresswoman Alexandira Ocasio-Cortez — commonly known as AOC — a Democrat from New York, was the first to call for impeachment over the Iran strike.

"The President's disastrous decision to bomb Iran without authorization is a grave violation of the Constitution and Congressional War Powers," AOC wrote on X on Saturday after the news broke. "He has impulsively risked launching a war that may ensnare us for generations. It is absolutely and clearly grounds for impeachment."

But many Republican lawmakers are backing Trump's decision.

House Speaker Mike Johnson took to X to voice his support: "The military operations in Iran should serve as a clear reminder to our adversaries and allies that President Trump means what he says," Johnson wrote.

Republican leader in the Senate John Thune also commended the military operation and called it a necessary check on Iran's ambitions of developing a nuclear weapon.

According to The New York Times, both Thune and Johnson were briefed before the strike took place.

Republican lawmakers argued that the strike will not drag the US into a prolonged war and the US will not deploy ground forces in the region as a result of the strike.

"To those concerned about US involvement—this isn't a 'forever war' in fact, it's ending one," Republican Senator Markwayne Mullin from Oklahoma wrote on social media.

Numerous Democratic lawmakers, even some Republicans, condemned the strike as "unconstitutional" because only Congress can authorize action to go to war.

"I am open to the idea that the US should attack Iran. But I am not open to the idea that Congress cedes all authority to the executive branch," Illinois Representative Sean Casten, a Democrat, posted on X, also calling Trump's action "impeachable".

"This is not about the merits of Iran's nuclear program. No president has the authority to bomb another country that does not pose an imminent threat to the US without the approval of Congress. This is an unambiguous impeachable offense," Casten wrote.

Texas Representative Al Green and Michigan Representative Shri Thanedar have been trying to introduce articles of impeachment against Trump, but they haven't got much support within the party.

Some Republicans also opposed Trump's move against Iran. "This is not Constitutional," Republican Representative Thomas Massie posted on X.

Massie and Democrat Ro Khanna introduced a bipartisan War Power Resolutions bill last week to require Congress to vote for US involvement in Israel's war with Iran.

"When two countries are bombing each other daily in a hot war, and a third country joins the bombing, that's an act of war," Massie posted. He said the bill aims to "prevent America from being dragged into another endless Middle East war."

Other members of Congress also worried that Trump might get the US involved in the Israel-Iran war. Senator Bernie Sanders last week also introduced a bill called No War Against Iran Act to prohibit the use of federal funds for any use of military force in or against Iran absent specific Congressional authorization.

"Netanyahu's reckless and illegal attacks violate international law and risk igniting a regional war. Congress must make it clear that the United States will not be dragged into Netanyahu's war of choice," Sanders said in a statement. "Another war in the Middle East could cost countless lives, waste trillions more dollars and lead to even more deaths, more conflict, and more displacement."

When news of the strike broke on Saturday, Sanders was at a "Fight Oligarchy" rally in Tulsa, Oklahoma. He read a sentence from Trump's statement to the crowd: "'We have completed a successful attack on three nuclear sites in Iran,' etc. etc."

The crowd erupted by shouting "boo" and chanting "no more war" repeatedly.

In Texas, Governor Greg Abbott issued a statement that Texas has elevated readiness in the event of any retaliatory response occurring in Texas.

"To ensure the highest level of safety in our communities, and out of an abundance of caution, Texas is elevating the readiness of our Texas Department of Public Safety troopers and Texas National Guard, increasing patrols around high-risk locations and ensuring our state is fully prepared to address any threat," Abbott said in a statement.