Antidoping officials from at least 10 nations and 20 athlete groups are preparing the extraordinary step of requesting that the entire Russian delegation be barred from the Summer Olympics over allegations of a state-sponsored doping program, according to email correspondence obtained by The New York Times.
The antidoping officials and athletes were expected to pressure Olympic leaders on the matter as soon as Monday — less than three weeks before the opening ceremony in Rio. They were waiting for the results of an investigation into claims published in The Times of a state-sponsored doping program conducted by Russian officials at the 2014 Sochi Olympics.
Grigory Rodchenkov, Russia's former antidoping lab director, told The Times in May that he followed government orders to cover up the widespread use of performance-enhancing drugs by dozens of Russian Olympians at the Sochi Games. At least 15 of them won medals, he said.
Russian officials have dismissed allegations of a state-run doping program as a Western conspiracy intended to smear Russia. The country's track and field team has already been barred from the Rio Games for doping violations; calls for sanctions against Russian athletes in every sport would be unprecedented and would likely escalate the geopolitical debate.
At least 10 national antidoping organizations — including those in the United States, Germany, Spain, Japan, Switzerland and Canada — and more than 20 athlete groups representing Olympians from around the world have banded together as they anticipate validation of Dr. Rodchenkov's claims.
The chief executive of the Institute of National Anti-Doping Organizations, a trade group to which dozens of nations' antidoping agencies belong, urged all members to sign on to the request on Friday, according to an email reviewed by The Times.
"It seems very likely that the Report will confirm what will be one of the biggest doping scandals in history, implicating the Russian Government in a massive conspiracy against the clean athletes of the world," wrote Joseph de Pencier, the chief executive of the national antidoping trade association. "This will be a 'watershed moment' for clean sport."
In an interview on Saturday, Travis Tygart, head of the United States Anti-Doping Agency, said: "We're not asking for the worst, and obviously we hope there's no doping going on by states. But if we're not preparing for all potential outcomes, then we're not fulfilling our promise to clean athletes."
Reuters first reported on Saturday that United States and Canadian antidoping officials were planning to call for a wider ban of Russian athletes at the Rio Games.
Mr. Tygart and other antidoping officials said they had not seen the report, which was commissioned by the World Anti-Doping Agency and prepared by a Canadian lawyer, Richard McLaren. It is expected to be released on Monday morning in Toronto.
Mr. McLaren has indicated that his inquiry will prove true what Dr. Rodchenkov told The Times last spring.
Last month, Mr. McLaren delivered a preliminary report to global track and field officials as they were scrutinizing Russia; he called Dr. Rodchenkov's detailed account of swapping out steroid-tainted urine at Sochi with the help of Russia's intelligence service "credible and verifiable," adding that he had evidence to confirm that "the ministry of sport was involved in instructing the laboratory to not report positive sample results."