LOS ANGELES — The One Championship mixed martial arts promotion says it has traded welterweight veteran Ben Askren to the UFC for former flyweight champion Demetrious Johnson.

One Championship CEO Chatri Sityodtong announced what is thought to be the first major trade in MMA history Saturday on Twitter.

Both fighters were released from their current contracts, allowing them to sign with their new promotions.

Johnson reigned as the UFC's only 125-pound champ from the inception of the division in September 2012 until last August, when Mighty Mouse lost a split decision to Henry Cejudo. Johnson is considered one of the world's top fighters, but he never became a North American star.

Askren is one of the best wrestlers in MMA. The Wisconsin native has fought in Asia since joining One Championship in 2014.