Phelps, still in China after winning eight gold medals at the Olympics, said, "We're definitely going to start training back in Baltimore.
"But I'm not really sure exactly. I never know what I'm really talking about, I just say things."
A day earlier, Phelps told NBC's Nightly News that he and his coach, Bob Bowman, had bought a pool in Baltimore and were looking to change the sport of swimming. Phelps and his representatives are in preliminary talks with management at the North Baltimore Aquatic Club to buy the Meadowbrook facility.
In April, Bowman was named the NBAC's chief executive officer, and he is expected to start the position next month.
At yesterday's news conference, Bowman, sitting next to Phelps, said he would not confirm or deny any looming deal, adding, "There are plans to expand our facilities. We have a lot of options for that, quite honestly. But nothing has been done with them."
One possibility has Phelps and his representatives also purchasing a neighboring ice-skating rink and post office to turn the area into an Olympic training center.
Officials from Northwest Skating Rink have not returned phone calls seeking comment. But some of the rink's instructors have been informed by management of the rink's closure, which is expected at the end of this month.
Fellow Olympic swimmer Katie Hoff, also at the news conference in China, said she had heard speculation about the NBAC expansion.
"That would be nice," she said. "I heard something about the ice rink being turned into [a pool], but I don't know. I really don't know anything. I've been kind of in my own little world for the past month or two."