By Matt Egan, NBC2 News.

NEW YORK (CNNMoney) -- Carl Icahn says it's "absurd" that Elizabeth Warren and other Democrats are claiming his new role as President Trump's regulation-buster creates a serious conflict of interest risk.

"I think that's completely ridiculous. I don't talk to Donald that often," Icahn told CNNMoney in a phone interview on Tuesday.

The billionaire investor said his financial interests -- such as a major stake in an oil refiner subject to EPA regulation -- shouldn't prevent him from advising Trump.

"Would you say that Jamie Dimon, who knows banking, shouldn't talk to him because he also owns bank stocks? It's absurd to say that," Icahn said, referring to the JPMorgan Chase CEO.

Others don't agree. A watchdog group filed a complaint on Wednesday alleging that Icahn broke lobbying rules by using his new role to push the White House to change the EPA regulations that are hurting oil refiner CVR Energy.

Icahn was one of Trump's earliest supporters on Wall Street and after the election the new president tapped him to help get rid of "strangling regulations" that are hurting the American economy.