FIFA has written to the Nigerian Football Federation to seek clarification over reports that lesbians have been banned from playing in the West Africa nation.
A spokesperson for the world governing body told CNN Friday that a letter had been sent requesting more information.
"This is not a FIFA investigation, but a preliminary step, fully in line with how any normal procedure would be conducted by FIFA's Disciplinary Department," the spokesperson said.
"Until we establish more details, we cannot speculate on any sanctions, or indeed any next steps."
Earlier this week, reports in Nigeria quoted Dilichukwu Onyedinma, head of the country's women's football league, who said lesbian players should be ostracized.
"Any player that we find is associated with it will be disqualified," she was quoted as saying.
"We will call the club chairmen to control their players, and such players will not be able to play for the national team."
Her reported comments drew a storm of protest for Gay Rights campaigners, and a number of groups said they had written to FIFA president Sepp Blatter about the alleged ban.
"The organizations expressed their concern about reports that the Nigerian Football Association has banned lesbians from football in the country," the Federation of Gay Games website reported.
"This follows reports that the coach of the Nigerian team participating in the 2011 FIFA Women's World Cup in Germany explained that she had excluded players presumed to be lesbians from the team.
"Given the inaction of FIFA following that situation, and the flippant response from FIFA to concerns over their decision to host future World Cups in homophobic countries, the organizations sending this letter believe that FIFA must now take firm action or confirm its reputation as a homophobic organization, in contradiction to its bylaws and the Olympic Charter."
Article 3 of the FIFA Statutes threatens stiff punishments for individuals or national federations if the code, which focuses on discrimination and racism, is broken.
"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," it reads.
Any action which FIFA might choose to take could be complicated by Nigerian law, under which homosexuality is already illegal.