Pablo Martinez Monsivais/AP

President Trump called for Sen. Mitt Romney to be "impeached" in a tweet Saturday after the Republican from Utah criticized the President for urging Ukraine and China to investigate his political rival.

"I’m hearing that the Great People of Utah are considering their vote for their Pompous Senator, Mitt Romney, to be a big mistake. I agree! He is a fool who is playing right into the hands of the Do Nothing Democrats! #IMPEACHMITTROMNEY," Trump tweeted.

Trump's tweet immediately drew questions on Twitter from people curious as to whether a senator can be impeached. The short answer is: no.

Senators and members of Congress can’t be “impeached” but they can be “expelled," according to Article 1, Section 5, of the US Constitution.

The article states: “Each House [of Congress] may determine the Rules of its proceedings, punish its members for disorderly behavior, and, with the concurrence of two-thirds, expel a member."

According to Senate.gov, since 1789, the Senate has expelled only 15 members, most for supporting the Confederacy during the Civil War.

It’s not clear what Trump thinks Romney could be “impeached” or, in this case, expelled for.

Some context: The criticism of Trump from a Republican senator comes as most congressional Republicans have remained silent and declined to speak out in opposition to the President's comments on Thursday that he wants both Ukraine and China to investigate Joe Biden and his son Hunter despite there being no evidence of wrongdoing.

Read Trump's tweet below: