Amir Khan has voiced his frustration at Floyd Mayweather Jr's decision to fight Andre Berto in what could be the American's final bout.

Following his defeat of Manny Pacquiao in May, Mayweather suggested that his next fight would be his last, with Khan believed to be a contender.

However the unbeaten American has instead opted to fight the two-time welterweight champion Berto, much to Khan's dismay.

"I'm disappointed not to have got the fight for what is the third time after having been one of the frontrunners," the Brit said in a statement.

"However, there are many big fights out there for me and I'm going to continue working hard to establish myself at the top of the welterweight division.

"Floyd Mayweather has fought the biggest names throughout his career and has earned the right to face whoever he chooses."

Mayweather will take on Berto at the MGM Grand in Las Vegas on September 12.