Olympian Matthew Mitcham has described a Russian law that prohibits the public promotion of gay rights as “horrific.”

Russian President Vladimir Putin in June signed the so-called “gay propaganda” law, which prohibits the positive portrayal of gay men and lesbians in a venue where minors might be present. It effectively outlaws everything from Gay Pride marches to the simple act of wearing a rainbow pride pin in public.

Some gay activists have called for a boycott of next year's Winter Olympics to take place in Sochi.

The 25-year-old Australian gold medal-winning diver came out gay shortly before attending the 2008 Beijing Games.

(Related: Gay Olympic diver takes the gold.)

“It's really sad,” Mitcham told UK daily The Telegraph. “The way they are persecuting people in Russia is quite horrific. “The Olympics is the best experience you will ever have as an athlete. Their whole memory and experience is going to be marred by this stuff. They are going to be made to feel unacceptable, inappropriate, and it is a really awful, awful feeling.”

He continued: “The Olympics are supposed to be somewhere where they can go to be relieved of that feeling. A place where you can compete and feel that gender and sexuality is not an issue.”

(Related: Blake Skjellerup, Johnny Weir Oppose Olympic boycott over Russian anti-gay law.)