• Weld said the death sentence was "the only penalty" for treason.
  • The former Massachusetts governor made the astonishing remarks during a joint MSNBC interview on "Morning Joe" alongside Joe Walsh and Mark Sanford, both former congressmen who are also mounting longshot presidential bids to wrest the GOP nomination away from Trump.
  • "That's not just undermining democratic institutions. That is treason. It's treason pure and simple," Weld said. "And the penalty for treason under the US code is death. That's the only penalty."
  • Business Insider's GOP presidential debate will run from 7 PM to 8:30 PM EST on September 24, and will be exclusively live-streamed on Business Insider Today's Facebook Watch page.
  • Visit Business Insider's homepage for more stories.

Republican presidential candidate Bill Weld accused President Donald Trump of treason for repeatedly urging the Ukrainian president to investigate former vice president Joe Biden and his son and said the death sentence was "the only penalty."

Weld made the astonishing remarks during a joint MSNBC interview on "Morning Joe" alongside Joe Walsh and Mark Sanford, both former congressmen are also mounting longshot presidential bids to wrest the GOP nomination away from Trump.

"That's not just undermining democratic institutions. That is treason. It's treason pure and simple," Weld said. "And the penalty for treason under the US code is death. That's the only penalty."

The former Massachusetts governor went on: "The penalty under the Constitution is removal from office and that might look like a pretty good alternative for the president if he could work out a plea deal."

He later doubled down on impeaching Trump, blasting him as "a lawless man" and said he had met the threshold of "high crimes and misdemeanors" that's mandated under the constitution.

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Weld and Walsh are set to face off in a livestreamed GOP primary debate organized by Business Insider on Tuesday, September 24. Sanford declined the invitation to attend.

Weld's remarks come as Trump has been engulfed in a firestorm after the Wall Street Journal reported on Friday that Trump urged the Ukrainian president to investigate Biden and his son, Hunter Biden, over possible corruption in Ukraine several years ago. After initially denying it, Trump acknowledged he discussed the Bidens over the weekend.

No evidence has emerged to substantiate the president's claims, which has been fueled by his conservative allies.

Business Insider's GOP presidential debate will run from 7 PM to 8:30 PM EST on September 24, and will be exclusively live-streamed on Business Insider Today's Facebook Watch page.

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