Billionaire investor Carl Icahn said Friday he has stepped down as a special adviser to President Trump on regulatory reform.

Icahn has been criticized by Democrats who said his advisory role created a conflict of interest because he had not taken a formal government job and was still running his businesses.

He said in a letter to Trump that he was stepping aside with the president’s “blessing” and “because I did not want partisan bickering about my role to in any way cloud your administration.”

In March, Icahn told CNNMoney that the conflict allegations were “absurd” and “completely ridiculous.” He added, “I don’t talk to Donald that often.”

CNNMoney (New York) First published August 18, 2017: 5:20 PM ET