"I recently did an interview with RT and was unaware they are a registered foreign agent. I regret doing the interview and apologize for allowing myself to be taken advantage of", Atlas wrote in a tweet on Sunday.
The controversial healthcare adviser went on to apologise to the national security community "who is working hard to defend us".
Atlas was featured in a 27-minute interview on the RT programme "Going Underground" where he discussed the White House's COVID-19 response and the widespread denunciation of his expertise. Atlas has been called a pseudo-expert and "off-the-rails" by Bill Gates, while the White House coronavirus point man, Anthony Fauci, has distanced himself from Atlas.
RT was forced to register as a foreign agent in the United States in the wake of the 2016 presidential election when Washington was gripped by a bout of suspicion of Russian influence on US politics, something Moscow has denied.