Amir Khan-Lamont Peterson rematch off after failed drugs test

Peterson tested positive for synthetic testosterone after both fighters agreed to random testing before their 19 May light-welterweight bout in Las Vegas.

WBA and IBF champion Peterson then gave a negative test, prompting his camp to appeal to the Nevada Athletics Commission for the fight to go ahead.

"This has upset me because I wanted to settle the score," Khan told BBC Sport.

"They should at least give those world titles back [to me].

"I'm upset for the fans. There were over 5,000 people who were travelling to Las Vegas and there is going to be no fight there. It is a little bit disappointing. I feel for them. I wanted to win that fight for the fans."

Golden Boy Promotions chief executive Richard Schaefer - Khan's promoter - confirmed earlier this week that Peterson tested positive from the A and B samples taken in March, but then gave a negative test in follow-up samples from 13 April.

Schaefer said he was disappointed he had not been made aware earlier of key information regarding Peterson's drugs test, leaving little time for an alternative opponent to be found.

"For Amir, it's a big blow," he said. "It's a big blow for fight fans and for the sport. Team Khan are all here in Los Angeles.

"Within the next 24 hours we are trying to identify a new date and a new opponent and potentially a new venue. Obviously, the opponent will not be Lamont Peterson.

"What is further shocking is that Team Peterson and the agency that conducted the drug testing - the Voluntary Anti-Doping Agency - did not give us the information that Peterson had tested positive back in April - 12 April to be exact.

"They waited until this Monday to disclose that to us. That put everybody in an extremely unfortunate position, because it does not give us enough time to find a proper replacement with little more than a week to go."

Peterson's team defended their boxer and pledged to clear his name.

"Team Peterson is very disappointed and distraught by the decision to cancel the 19 May rematch against Amir Khan," they said.

"This is an extremely difficult decision to accept. We did everything that was asked of us in efforts to comply. To support our stance we provided the Nevada State Athletic Commission with a significant amount of factual medical data in response to these allegations.

"Lamont did a battery of tests this week and saw a number of independent board certified physicians. They all had the exact same conclusion as the doctor that initially treated and diagnosed Lamont's medical condition.