Michael Phelps speaks after a practice session, Wednesday, April 15, 2015, in Mesa, Arizona, US. [Photo/IC]

MESA - Michael Phelps is aiming to compete in a fifth Olympics next year in Rio, although the 18-time Olympic champion won't swim in the world championships this summer.

Phelps confirmed his intention to make one last run at the Olympics on Wednesday.

"You guys heard it here first," he told reporters at Skyline Aquatic Center, where he will be competing in his first meet since serving a six-month suspension by USA Swimming after a second drunken driving arrest last fall. "I am looking forward to next year. I don't think it's too hard to really realize why I came back."

But Phelps said he won't be swimming at the world meet in Russia in August as part of the punishment set forth by the sport's US governing body. He had already qualified in three events before being banned from the last major international meet before the Rio de Janeiro Olympics.

"I really enjoy being on those trips," he said. "That's why it is painful to think that I won't have the chance to compete at worlds."

There had been informal discussions about Phelps being reinstated to the US team for worlds, but it would have meant removing swimmers that were named to the team in his absence.

"By no means do I want this to be a distraction from the team," he said. "No way would I ever want to displace a member of that team."

Instead, he plans to compete at US summer nationals in San Antonio, Texas, during the same time as worlds.

Phelps is back in Arizona, where he attended 45 days of inpatient alcohol rehabilitation after being arrested on DUI charges in his hometown of Baltimore last September. He offered no specifics about his treatment, which he continued in Maryland. He also enrolled in Alcoholics Anonymous.

"The last couple of months have probably been the hardest I've ever had to go through in my entire life," he said. "I take full responsibility for all of my actions. I've hurt a lot of people and it's been terrible."

The 29-year-old swimmer was sentenced to 18 months of probation. He said he's done more growing up in recent months than he has in his entire life.

"I have been able to come out on a better end, have a clear head," he said. "I don't think I've ever been like this once in my life."