Olympic swimming champion Michael Phelps has refused to say whether or not biological males should be allowed to compete in women’s sports, arguing that the situation is “complicated.”

Speaking CNN’s Christiane Amanpour, the decorated athlete addressed the controversy surrounding transgender UPenn swimmer Lia Thomas, a man living as a woman. Phelps said that the authorities will need to develop rules that make the competition an “even playing field.”

“I can talk from the standpoint of doping,” Phelps said. “I don’t think I’ve competed in a clean field in my entire career. So, I think this leads back to the Organising Committees again because it has to be a level playing field. I think that’s something that we all need.

“I don’t know where this is going to go. I don’t know what’s going to happen. I believe that we all should feel comfortable with who we are in our own skin,” he added. “But I think sports should all be played on an even playing field.”

Phelps said the future of women’s sports will be “very complicated” while refusing to make a declarative statement.

“I don’t know what that looks like in the future. But it’s hard. It’s very complicated,” he said.

“This is my sport. This has been my sport my whole entire career. Honestly, the one thing I would love is everybody to be able to compete on an even playing field. That’s all I can say,” he added.

Lia Thomas, who previously competed for the UPenn men’s team for three seasons as Will Thomas, became a controversial figure late last year when he dominated the competition at the Akron Zippy Invitational, smashing university records and pool records when he won the 1650 race by a whopping 38 seconds over his teammate.

Some female swimmers lamented that Thomas began boasting about the ease of his victory following the competition.

“That was so easy, I was cruising,” a female swimmer reported Thomas as saying. “At least I’m still No. 1 in the country.”

Parents and several athletes protested that Lia Thomas had an unfair advantage and demanded that the NCAA put a stop to it. Late last month, one swimming official even publicly quit in protest.

Though the NCAA has largely backed Lia Thomas and transgender athletes in general throughout the controversy, the organization’s board of governors will convene this Thursday to discuss the current policy, according to SwimSwam.com.

“The Board of Governors cannot directly enact legislation, but can provide guidance and recommend legislation to each division, where it is reviewed in the divisions’ legislative processes,” noted the outlet.

The upcoming meeting comes after the American Swimming Coaches Association called on the NCAA to review its current policy on transgender athletes.

The American Swimming Coaches Association urges the NCAA and all governing bodies to work quickly to update their policies and rules to maintain fair competition in the women’s category of swimming. ASCA supports following all available science and evidenced-based research in setting the new policies, and we strongly advocate for more research to be conducted.

ASCA embraces and encourages diversity and believes all people should have the opportunity to participate in swimming. Transgender people belong in our sport and have every right to compete, and at the same time cisgender females have a right to a category of competition that is fair and meaningful.

The current NCAA policy regarding when transgender females can compete in the women’s category can be unfair to cisgender females and needs to be reviewed and changed in a transparent manner.

The discrimination and disrespect that has erupted as a result of this conversation has no place in our sport or in society. We strongly reject the criticism of the athletes and coaches who are merely following the rules.

Both UPenn Athletics and the Ivy League have voiced support for Lia Thomas.