MOSCOW (Reuters) - Russian sports minister Vitaly Mutko was surprised by a draft letter by the United States Anti-Doping Agency calling for a complete ban on Russia competing at the Rio Olympics, he was quoted as saying by TASS news agency on Sunday.

In a leaked draft letter to the International Olympic Committee, to be sent once the report into allegations of state-backed doping at the 2014 Sochi winter Olympics led by Canadian law professor Richard McLaren is presented on Monday, the U.S. agency's CEO Travis Tygart called for a ban on all Russian athletes.

"The McLaren report is yet to be published, but for them (USADA) everything is already clear. This is surprising. May be it was Tygart who wrote the report himself? I would not be surprised," Mutko told TASS.

(Reporting by Katya Golubkova; Editing by Andrew Heavens)