Women have expressed outrage as female athletes from Japan's football team and Australia's basketball team fly economy to the Olympics while their male counterparts travelled business class.
The Japanese and Australian teams have been accused of sexism and imposing double standards on their athletes.
Despite being strong contenders for the gold medal, Japan's women's world-beating soccer team had to fly premium economy to London while the lower-ranked men's team enjoyed business class.
The team's star player Homare Sawa, who led Nadeshiko to victory in the women's world cup last year and was named Fifa women's world player of the for 2011, told Japanese media that the way the teams travelled "should have been the other way around."
Speaking to Japanese media, she said:
"When we won the world cup, our seats were changed to business class for our return flight.
"I hope we can produce a good result again and be treated the same way."
The Australian women's basketball team also had different travel arrangements to the men's squad. The Opals were upgraded from economy to premium economy, while the men were treated to business class for the long-haul trip to London.
The Australian Olympic Committee told Channel 4 News that the Opals and the Boomers did fly in different classes, but they were on different planes.
"It's a Basketball Australia decision.
"The IOC provides all teams with economy airfares, but sports teams can pay extra or use points to upgrade if they want," a spokesman said.
The row over gender bias comes after the IOC hailed the London 2012 Games as "an historic step towards gender equality" as Saudi Arabia, Qatar and Brunei are, for the first time in history, sending female athletes to compete in the Olympics.
Ove the years the Olympic Games have seen female participation rise from 1.8 per cent at London 1908 to 9.5 per cent at London 1948 and more than 42 percent at Beijing 2008.