Elton John has urged Russia to end discrimination against gays as he performed at a concert in Moscow.
The British singer said he was "sad to learn" of a law banning the "propaganda of homosexuality" to minors.
The loosely-worded law can be used to ban gay rights events, critics say.
Sir Elton became the first major Western star known for his support of gay rights to play in Russia since the law was signed by President Vladimir Putin in June.
Last year, both Madonna and Lady Gaga used concerts in Saint Petersburg to speak out against similar local legislation.
'Obliged' to perform
The singer reportedly interrupted his Friday show to voice his concerns about the legislation.
"In my opinion, it is inhumane and it is isolating," he was quoted as saying.
The concert was dedicated to Vladislav Tornovoi, a 23-year-old man tortured and murdered in the southern city of Volgograd earlier this year, Russia's Interfax news agency reports.
Sir Elton will play a second Russian concert in the Volga city of Kazan later on Saturday.
Russian promoters, SAV Entertainment, had earlier insisted the two concerts would "go ahead as planned" despite concerns over the country's crackdown on gay rights.
"Despite the groundless rumours spread by the internet and media that Elton John's concerts in Russia could be cancelled, the organiser assures you that Elton John's shows in Moscow and Kazan will go ahead as planned," they said.
Elton John publicly said he was gay in 1988 and is in a civil partnership with David Furnish, with whom he has two children born to a surrogate mother.
In September he told The Guardian that he felt an obligation to perform in Russia so that gay men and women living there did not feel like they were in "an isolated situation".
"As a gay man, I can't leave those people on their own without going over there and supporting them," he told the newspaper.
"I don't know what's going to happen, but I've got to go."
Gay athletes welcome
In Russia, groups such as the Union of Orthodox Brotherhoods and the Ural Parents Committee have publicly spoken out against Sir Elton performing in the country, either through a petition or a letter to Mr Putin.
Russia decriminalised homosexuality in 1993, but its medical institutions continued to class homosexuality as a mental disorder until 1999.
A survey by Levada independent polling centre in March found that 34% thought homosexuality was an illness that should be treated.
With next year's Winter Olympics due to be held in Sochi in Russia, the current law has attracted attention around the world.
However Mr Putin said in October that gay "athletes, fans and guests" would be made to feel welcome during the games.