Billionaire oilman Harold Hamm said Thursday he has suggested that President-elect Donald Trump should nominate Rep. Kevin Cramer, R-N.D., for Energy secretary.

Hamm, an energy adviser to Trump, has long been seen as a candidate for the position, but he has repeatedly said he already has a full-time job running Continental Resources. The company made its name proving crude oil could be profitably extracted from shale rock in North Dakota using advanced drilling methods.

Cramer has said Hamm should have the right of first refusal for Energy secretary, but Hamm told CNBC that Cramer is the man for the job.

"Kevin's a great guy, and he would be a perfect candidate, as well. I've put his name forward," Hamm said on "Squawk on the Street." "He'd sort of do a better job in that post than me."

Prior to being elected to Congress in 2012, Cramer was North Dakota's energy regulator in his role as public service commissioner. His tenure overlapped with a boom in oil production in the state fueled by drilling advances pioneered by companies like Continental Resources.

Cramer has also advised Trump on energy policy. His nomination would likely draw criticism from Democrats, environmentalists and progressives because he describes himself as a climate-change skeptic. He has, however, expressed support for a moderate carbon tax, which would aim to rein in greenhouse gas emissions.

Trump has already drawn fire for putting prominent climate-change denier Myron Ebell in charge of staffing the Environmental Protection Agency.