Can Donald Trump serve a third term as US president?

Highlights:

• Trump floats possibility of third term
• Constitution has limited presidents to two terms since 1951
• Republicans lack majority needed to change Constitution

President Donald Trump said on Sunday he was not joking about seeking a third term but did not explain how he would get around the US Constitution's prohibition against anyone serving more than two terms as president.

Here is a look at the legal barriers Trump faces.

WHAT DOES THE CONSTITUTION SAY?

The 22nd Amendment states in part: "No person shall be elected to the office of the President more than twice."

The amendment was ratified in 1951 after President Franklin D. Roosevelt broke with a self-imposed two-term limit set by presidents since George Washington, the nation's first.

Roosevelt, a Democrat who was president during the Great Depression and World War Two, served a third term and then died months into his fourth term in 1945.

Wayne Unger, a law professor at Quinnipiac University, said the Constitution was clear that presidents are limited to two terms of four years each. He said that while that had not been tested in court, any challenge by Trump would likely be unsuccessful.

"I would predict the Supreme Court to say nope, it's clear, two terms of four years each, Donald Trump, you cannot run for a third," said Unger, who teaches constitutional law.

CAN TRUMP'S ALLIES CHANGE THE CONSTITUTION?

Yes, but that is highly unlikely in an era of intense political polarization between Democrats and Trump's Republican Party.

Any constitutional amendment would require two-thirds support in the House and Senate or a convention called by two-thirds of the states, and then ratification by 38 of the 50 state legislatures.

Republicans hold a razor-thin 218-213 majority in the House and a 53-47 majority in the Senate. Republicans control 28 state legislatures.

Andy Ogles, a Republican US representative from Tennessee and a strong Trump supporter, in January proposed amending the 22nd Amendment to allow people to serve three non-consecutive terms as president.

Since Trump's terms beginning in 2017 and in 2025 were non-consecutive, the amendment if passed would allow him to serve a third term starting in 2029.

COULD TRUMP RUN AS VICE PRESIDENT?

In an interview with NBC, Trump said one possibility would be for his vice president, JD Vance, to run for president in 2028 with Trump as his vice presidential candidate.

Vance would then resign as president if he wins, paving the way for Trump to return to the White House.

But Trump is barred from running for vice president because he is not eligible to be president. The 12th Amendment to the US Constitution reads, "No person constitutionally ineligible to the office of President shall be eligible to that of Vice-President of the United States."