The U.S. Olympic Committee (USOC) has said it was "disappointed in the behavior recently exhibited by Michael Phelps."
"Michael is a role model, and he is well aware of the responsibilities and accountability that come with setting a positive example for others, particularly young people," the USOC said in a statement emailed to Xinhua on Monday.
"In this instance, regrettably, he failed to fulfill those responsibilities," the statement said.
The USOC made the statement after a photo of Phelps inhaling from what appears to be a marijuana pipe was published in a British tabloid. Phelps won eight swimming gold medals in the Beijing Olympic Games last summer.
The Olympian made a quick apology over the weekend, saying: "I engaged in behavior which was regrettable and demonstrated bad judgment. I'm 23 years old and despite the successes I've had in the pool, I acted in a youthful and inappropriate way, not in a manner people have come to expect from me."
"Michael has acknowledged that he made a mistake and apologized for his actions," the USOC statement said.
"We are confident that, going forward, Michael will consistently set the type of example we all expect from a great Olympic champion," the statement added.
(Xinhua News Agency Feburary 3, 2009)