Washington DC - More than 80 US lawmakers have called for President Donald Trump to be removed from office over his violent threats to Iran.

Calls to invoke the 25th Amendment to oust Trump grew loudest after the president wrote on Truth Social that "a whole civilization will die tonight, never to be brought back again," hours before his deadline for Iran to reopen the Strait of Hormuz was due to expire.

The blatantly genocidal threat was the culmination of a series of increasingly unhinged posts that drew the ire of both Democrats and prominent members of Trump's MAGA base. Despite a last-minute temporary truce being agreed, the anger has not subsided.

Besides standard impeachment proceedings in Congress, there is a quicker option to oust Trump, the 25th Amendment to the Constitution.

According to Section 4 of the Amendment, a president can be removed from office if they are declared "unable to discharge the powers and duties of his office."

However, the provision has never been applied before and it appears unlikely that it will be now, as Vice President JD Vance as well as a majority of cabinet members would have to transmit a written declaration to this effect to the president of the Senate and the speaker of the House.

As president, Trump would be able to object, but Vance and the Cabinet members would in theory be able to override his veto, leaving the decision up to Congress.

Lawmakers would have up to 21 days to vote, with the vice president serving as president in the meantime.

In order to impeach the president, a two-thirds majority would be required in both chambers, meaning Democrats would need support from Trump's Republicans as well as his own Cabinet.