Former Massachusetts Governor and Republican presidential challenger Bill Weld said Monday that President Donald Trump’s “acts of treason” in pressuring Ukraine President Volodymyr Zelenskyy to investigate former Vice President Joe Biden deserved the death penalty.

“That is treason. It’s treason pure and simple, and the penalty for treason under the U.S. code is death,” Weld told MSNBC’s Morning Joe. “That’s the only penalty.”

Weld made the shocking statement in a joint appearance with fellow GOP presidential challengers Joe Walsh and Mark Sanford, who are protesting state Republican parties that have decided to cancel primaries to give the edge to the sitting president.

“Obviously, canceling primaries undermines democratic institutions and democratic elections, but that’s far from the deepest dive crime that the president has committed here,” Weld said, referring to the growing calls for clarification about Trump’s actions toward Ukraine and the withholding of military funds in the weeks before a July 25 call in which he admitted to discussing an investigation of Hunter Biden.

Biden’s son had business dealings in Ukraine at the same time then-Vice President Biden was tasked with overseeing the Obama administration’s Ukraine policy. Trump made the call when he already knew Biden would challenge him in the 2020 presidential election.

“He has now acknowledged that in a single phone call right after he suspended $250 million of military aid to Ukraine, he called up the president of Ukraine and pressed him eight times to investigate Joe Biden, who the president thinks is going to be running against him,” Weld said.

“Talk about pressuring a foreign country to interfere with and control a U.S. election.”

The death penalty is the maximum punishment for treason, but federal law also allows for lesser sentences including five-year prison terms or fines starting at $10,000. The law also states that treasonous acts can prohibit one from holding public office.

“The penalty on the Constitution is removal from office,” Weld said. “And that might look like a pretty good alternative to the president if he can work out a plea deal.”

Weld then backed off calls for executing the president, but only slightly.

“The grounds for removal of office, impeachment, are treason, bribery, or other high crimes and misdemeanors,” he said. “We don’t have to worry about bribery anymore, we don’t have to worry about other high crimes and misdemeanors, although I think he committed many. We have treason and we can go right for the hoop.”

Weld’s fellow guests did not immediately weigh in on calls for the death penalty for the president. Weld then called on fellow Republicans, especially those facing re-election for congressional seats, to speak out. “If they won’t say this is a bridge too far for us, then they really have no chance at the ballot box next year, not just President Trump but those members of the Senate,” he said.

“It’s well past time for this guy, in my opinion, to be carted off to save us all,” Weld said. “He’s daring us all to let him be totally lawless. He has no respect for the law, he has no knowledge base under any issues. Why do we want this man as president of the United States? I don’t get it.”