Legislation prohibiting "propaganda of nontraditional sexual relations among minors" has provoked an international furor since President Vladimir Putin signed it off in June and sparked growing concern at the IOC ahead of the Sochi Winter Games next February.
The two most influential organizations in world sports are both now asking Russia how the law would be enforced during their marquee events.
"FIFA has asked the Russian authorities for clarification and more details on this new law," football's governing body said in a statement Tuesday.
"Russia has committed to provide all visitors and fans with a warm welcome and ensure their safety" during the monthlong tournament, FIFA said, adding that "FIFA trusts that the 2018 FIFA World Cup hosts will deliver on this promise."
FIFA has a direct link to the Russian government, as Sports Minister Vitaly Mutko serves under FIFA President Sepp Blatter on the football body's 27-member executive board.
Mutko has said that Olympic athletes would have to respect the country's laws during the Feb. 7-23 Winter Games, and that international reaction needed to "calm down."
FIFA noted that its statutes "foresee zero tolerance against discrimination."
Article 3 states: "Discrimination of any kind against a country, private person or group of people on account of ethnic origin, gender, language, religion, politics or any other reason is strictly prohibited and punishable by suspension or expulsion."
Russia was awarded World Cup hosting rights in December 2010, when FIFA's board chose it ahead of England and joint bids from Spain-Portugal and the Netherlands-Belgium.
That same day in Zurich, FIFA awarded hosting of the 2022 World Cup to Qatar, where homosexual acts are illegal.
Blatter drew criticism soon after the World Cup votes when he suggested that gay football fans could "refrain from any sexual activities" while attending the World Cup in the Gulf nation.
In May, after FIFA member countries approved tougher sanctions for discrimination, Blatter was asked by reporters what gay fans and players could expect in Qatar, and said that he could not offer "a definite answer" at this stage.
The potential effect on the Sochi Olympics of Russia's attitude toward gay rights is playing out during campaigning for the six-man race to be elected IOC president on Sept. 10.
On Monday, candidate C. K. Wu of Taiwan said that "we are not joking" with Russia, and suggested that future bidders should be judged more strictly on their human rights record and follow the Olympic charter.
"This should become a basic qualification if you want to apply to host the games," Wu said.