The law, signed by President Vladimir Putin in June, bans "propaganda of nontraditional sexual relations" and imposes fines on those holding gay pride rallies. It has caused a major international outcry and spawned calls for protests ahead of the Feb. 7-23 Olympics in the Black Sea resort.
Rogge said the Russian government provided written re-assurances about the law on Thursday, but that some elements are still too unclear to pass judgment.
"We are waiting for the clarifications before having the final judgment on these reassurances," Rogge said, a day before the start of the world athletics championships in Moscow.
In Washington, President Barack Obama said it would be wrong to boycott the Winter Olympics despite frustrations with Russia.
At a White House news conference Friday, Obama said he is offended by Russia's new law. He added that American athletes are training hard and it wouldn't be fair to deny them the chance to compete at the games.
Russian Sports Minister Vitaly Mutko insisted Thursday that Olympic athletes would have to respect the laws of the country during the Sochi Games. On Friday, he said there was no way Russia would back down under political pressure.
Referring to Western criticism, Mutko was quoted as saying by Interfax: "I wouldn't call the pressure light. Russia must understand that the stronger we are, the more other people aren't going to like it. We have a unique country."
"We don't have to be afraid of threats to boycott the Olympic Games," Mutko said. "All sensible people understand that sports demand independence, that it is inadmissible that politics intervene."
On Thursday, Mutko did make it clear that the private lives and privacy of athletes would be respected as it is guaranteed by the Russian constitution
Rogge said that was essential.
"The Olympic charter is clear," Rogge said. "A sport is a human right and it should be available to all, regardless of race, sex or sexual orientation."
Even if Russia accepts that principle, the law leaves open the issue of athletes speaking freely during the games.
"As far as the freedom of expression is concerned, of course, this is something that is important," Rogge said. "But we cannot make a comment on the law" until the clarifications have been received.
The All Out advocacy group said it was happy with Rogge's comments.
"This is the strongest and most direct statement we have received from the International Olympic Committee. It shows the IOC is listening to the global outcry," said All Out Executive Director Andre Banks.
Still, Rogge pleaded for time to study the Russian reassurances some more.
"I understand your impatience to get the full picture, but we haven't (received) it today," Rogge said. "There are still too many uncertainties in the text."
Rogge said the problems seemed to centre on translations.
"We don't think it is a fundamental issue," he said at a news conference following a meeting of the IOC executive board with the International Association of Athletics Federations.
Associated Press writer Laura Mills contributed to this report.
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