COLORADO SPRINGS, Colo. -- Olympic swimming great Michael Phelps has been suspended for six months from USA Swimming-sanctioned competition after his arrest for driving under the influence in Baltimore last week.

In announcing the decision Monday, USA Swimming also said Phelps will be withdrawn from the 2015 FINA World Championships team and that he will forfeit his funding from the national governing board for six months.

"Membership in USA Swimming, and particularly at the National Team level, includes a clear obligation to adhere to our Code of Conduct," USA Swimming executive director Chuck Wielgus said in a statement. "Should an infraction occur, it is our responsibility to take appropriate action based on the individual case. Michael's conduct was serious and required significant consequences."

Phelps, 29, was charged last Tuesday with driving under the influence, excessive speed and crossing double lane lines in the Fort McHenry Tunnel on Interstate 95 in his native Baltimore, according to the Maryland Transportation Authority. His trial is scheduled for Nov. 19.

Phelps tweeted on Sunday that he would be taking time away to "attend a program that will provide the help I need to better understand myself."

"We think the sanctions are appropriate and we are glad that Michael is seeking help," U.S. Olympic Committee CEO Scott Blackmun said Monday. "We are grateful that nobody was hurt and appreciate the speed at which USA Swimming and Michael took action."