Since the start of the war with Iran more than a month ago, US President Donald Trump has repeatedly criticized NATO. In recent statements, Trump even said that he would consider withdrawing the country from the organization.

The military alliance was created in 1949 to "ensure a lasting peace in Europe and North America."

Despite Trump's claims that he could withdraw his country from the alliance, a law passed by Congress in 2023 states that "the President shall not suspend, terminate, denounce, or withdraw the United States from the North Atlantic Treaty," unless done "by the advice and consent of the Senate, provided that two-thirds of the Senators present concur, or pursuant to an Act of Congress."

In an interview with ABC's "This Week" last month, Senator Thom Tillis, the top Republican on the bipartisan Senate NATO Watch Group, said it's "not actually true" that Trump could withdraw from NATO without Congress.

"The president of the United States cannot withdraw from NATO. Now, by saying the president can poison the well, the president can make it functionally inoperable if he wants," he declared.

Tillis also defended NATO allies after Trump called them "cowards" who have not helped the US.

However, a 2020 legal opinion from the Justice Department's Office of Legal Counsel says the president has exclusive authority over treaties, CNN writes.

The US unilateral withdrawal from NATO could be finalized depending on a court's analysis, according to a report by the Congressional Research Service.