The president of the United States, Donald Trump, on Thursday threatened the death penalty for Democratic lawmakers who told members of the US military they should refuse to comply with illegal orders.

Earlier this week, six Democrats who have previously served in the armed forces or intelligence community published a video message in which they told current service personnel that the Trump administration was pitting them against the American people and threatening key tenets of the US Constitution.

"We know you are under enormous stress and pressure right now, but our laws are clear: you can refuse illegal orders," said Arizona Senator Mark Kelly, a former astronaut and Navy veteran.

"We need you to stand up for our laws, our constitution," added Michigan Senator Elissa Slotkin, a former CIA analyst and Iraq war veteran. "Don't give up the ship."

Trump: 'Seditious behavior' is 'punishable by death'

Trump reposted an article about the video on his Truth Social platform Thursday, calling it "SEDITIOUS BEHAVIOR, punishable by DEATH!"

Earlier, he had written: "This is really bad, and Dangerous to our Country. Their words cannot be allowed to stand. SEDITIOUS BEHAVIOR FROM TRAITORS!!! LOCK THEM UP???"

Asked at a news briefing whether the US president really wanted to execute members of Congress, White House spokeswoman Karoline Leavitt said "no" – but lambasted the lawmakers for encouraging service personnel to refuse to obey orders.

In response, Slotkin insisted that she and her colleagues would continue to defend the constitution, saying on X: "No threat, intimidation, or call for violence will deter us from that sacred obligation."

Democrats slam 'chilling behavior' 

Slotkin and her colleagues received support from fellow Democrats, including Senator Chris Coons of Delaware, the top Democrat on the Appropriations Subcommittee on Defense.

"Calling for the execution of senators and members of Congress … is chilling behavior we should expect from authoritarians ... not the president of the United States," he said. "Every one of my Republican colleagues needs to stand up and swiftly condemn this."

But his appeal was largely met with milder responses from Republicans.

"Well, that's his opinion," Senator Tim Sheehy, a Montana Republican and former US Navy SEAL, told Reuters news agency.

Senator Lindsey Graham, a South Carolina Republican, told reporters he "hated" the Democrats' video but called Trump's reaction "over the top."

"This is the most irresponsible thing I've seen from members of Congress," he said. "But what the president said, I don't agree with."

Could Trump really impose the death penalty on lawmakers?

It's not the first time that Trump has called for extreme, even capital, punishments for his political opponents.

In November 2021, Trump defended supporters who called for Vice President Mike Pence to be hanged as they stormed the US Capitol in the deadly January 6, 2021, riot months after Trump lost the 2020 presidential election to Joe Biden.

Since returning to the White House this year, Trump has called for imprisoning adversaries and his Justice Department has indicted critics, such as former federal officials John Bolton and James Comey.

US law makes no provision for "sedition" charges for civilians such as lawmakers, although "seditious conspiracy" is punishable by up to 20 years in jail.

For the military, however, the Uniform Code of Military Justice includes a section on sedition, with penalties up to and including death.

"When Donald Trump uses the language of execution and treason, some of his supporters may very well listen," said Senator Chuck Schumer. "He is lighting a match soaked with gasoline."

Edited by Sean Sinico