A decision on whether Russia will be subject to a total ban from the 2016 Olympics should come this week, according to the president of the Russian Olympic Committee (ROC).
Allegations of state-sponsored doping have cast serious doubt over the country's Rio prospects, with its track and field athletes already set to miss out.
The Court of Arbitration for Sport (CAS) will on Thursday deliver its verdict on Russia's appeal to overturn that IAAF-imposed ban.
And ROC president Alexander Zhukov expects a final decision from the IOC regarding a blanket suspension of Russian competitors to follow by Sunday.
"The issue will be finally resolved by the end of this week, probably on Sunday," he said at Wednesday's meeting of the ROC, where a 387-strong squad for the Games was approved.
Russia's chances of being present in Brazil suffered a further blow upon the publication of a report by professor Richard McLaren.
McLaren was appointed by the World Anti-Doping Agency to conduct an investigation into allegations of a doping cover-up in Russian sport, with the findings made public on Monday.
The report found that the country's government, security services and sporting authorities colluded to hide positive doping tests across a range of sports.
In light of the report, IOC president Thomas Bach said: "The findings of the report show a shocking and unprecedented attack on the integrity of sport and on the Olympic Games.
"Therefore, the IOC will not hesitate to take the toughest sanctions available against any individual or organisation implicated."