By Dmitriy Rogovitskiy
MOSCOW (Reuters) - A repeat drug test of Russian heavyweight Alexander Povetkin, who is the official challenger for the World Boxing Council (WBC) title, has returned a negative finding, the boxer's promoter said on Tuesday.
"We received Povetkin's new official tests. They are clean," Andrei Ryabinsky wrote on his Twitter feed.
On May 13, a doping test that Povetkin had given in April showed traces of meldonium.
Due to the breach, his WBC super heavyweight bout with Deontay Wilder of the United States, which was scheduled for Moscow on May 21, was postponed indefinitely.
"Now our opponents and some American journalists should apologize in front of us and also pay," Ryabinsky said, referring to criticism that Povetkin received after the original positive finding was announced.
Ryabinsky now wants the fight should take place by the end of the year.
Meldonium was added to the World Anti-Doping Agency's (WADA) list of banned substances on January 1.
On 13 April, WADA announced that tests taken before March 1, 2016, which showed the presence of less than one microgram of meldonium, would be acceptable, and would not lead to any punishment.
(Editing by Andrew Both)