President Donald Trump has raised concerns over his predecessor's use of an autopen, which is a mechanical device that allows an individual's signature to be copied onto a document.

Trump once again brought up the issue this week, alleging that an autopen was criminally used by "radical left lunatics" to "do anything they wanted."

Trump: Biden "didn't know what he was doing"

According to Newsmax, the president raised that allegation on Monday when he was interviewed by journalist Miranda Devine.

"The people who ran this country were radical left lunatics ... They didn't want [Biden]. They wanted Bernie Sanders," Trump told Devine.

"I think for the first two weeks [after Biden took office], they were really, really disappointed. They couldn't even believe it," he asserted.

"And then they realized that you had somebody that didn't know what he was doing. They could do anything they wanted because the autopen was the power," the president continued.

Trump alleged that "cognitively impaired" Biden was taken advantage of

The president's comments during his interview with Devine echoed similar statements which he made in a Truth Social post late last month.

"Joe Biden was not for Open Borders, he never talked about Open Borders, where criminals of all kinds, shapes, and sizes, can flow into our Country at will," Trump wrote.

"It wasn’t his idea to Open the Border, and almost destroy our Country, and cost us Hundreds of Billions of Dollars to get criminals out of our Country, and go through the process we are going through now," the president asserted.

"It was the people that knew he was cognitively impaired, and that took over the Autopen. They stole the Presidency of the United States, and put us in Great Danger," Trump continued.

Attorney general to investigate autopen use

Meanwhile, The Hill reported last week that Trump has instructed Attorney General Pam Bondi to investigate autopen use in the prior administration.

Specifically, she is to find out "whether certain individuals conspired to deceive the public about Biden’s mental state and unconstitutionally exercise the authorities and responsibilities of the President."

What's more, The Hill also noted that Department of Justice (DOJ) pardon attorney Ed Martin will begin reviewing the pardons that Biden issued to members of his family.

"The American people deserve to know the extent to which unelected staffers and an autopen acted as a proxy president due to the incompetence and infirmity of the previous president," White House spokesperson Harrison Fields was quoted as saying.