In a statement on the organization's website on Monday, the IOC revealed that two urine samples provided by Ostapchuk had tested positive for the presence of metenolone, which is classified as a banned anabolic agent.

According to the IOC, one sample was taken on August 5, the day before the shot put final, and the other right after Ostapchuk had finished competing in the final.

As a result of the positive tests, Ostapchuk has been disqualified from the shot put event, "excluded" from the London 2012 Olympics, and will have her gold medal withdrawn.

The medals will be redistributed among the three athletes that finished behind Ostapchuk. New Zealand's Valerie Adams, who was initially awarded the silver medal, will now receive gold, meaning she successfully defended her shot put gold medal from the 2008 Olympics in Beijing.

Russia's Evgeniia Kolodko now moves into second, and Lijiao Gong of China - who had finished outside the medals - will get bronze.

Ostapchuk could face further disciplinary measures from the International Association of Athletics Federations (IAAF), which could include a ban from competition.