Sir Ian McKellen has penned a letter to Vladimir Putin, signed by 27 Nobel laureates, asking the Russian president to change a law banning "homosexual propaganda".
Leading figures within the fields of arts and sciences have signed the letter, which was written to reveal the "politicians, artists, sports people and many others who have already expressed their abhorrence for the Russian government's actions against its gay citizens".
Geneticist Sir Paul Nurse and chemist Sir Harry Kroto also speak out in the open letter, which was sent to the Independent.
Sir Ian McKellen has long been an influential spokesman for Lesbian, Gay, Bisexual and Transgender (LGBT) rights. President Putin has come under extensive criticism for the law, which bans the spreading of "propaganda of nontraditional sexual relations to minors".
The letter comes just days before the start of the Winter Olympics in Sochi in Krasnodar Krai, Russia.
It reads: "The letter is written to indicate that many senior members of the international scientific community show solidarity with politicians, artists, sports people and many others who have already expressed their abhorrence for the Russian government's actions against its gay citizens.
"Protest is never easy but we hope that by expressing opposition to the new legislation it might be possible to encourage the Russian state to embrace the 21st century humanitarian, political and inclusive democratic principles which Mikhail Gorbachev worked so hard to achieve."
Sir Ian also writes of his previous visits to Russia, stating he will make clear his objections to the law in his next visit.
The letter reads: "I accepted an invitation some time ago to go to Russia in 2014 before this issue arose and although I have considered seriously cancelling my visit I have decided to go and while in Russia make my grave concerns clear at appropriate moments by pointing out that I shall not consider any further invitations unless this law is repealed or moves to repeal it are taken and in addition a serious effort is made by the Russian Government to ensure the safety of the Russian LGBT community."
In December, he told the Radio Times he was not able to go for fears over his safety. Gay rights supporters have been attacked for demonstrating in public, after the bill signed by Putin last June.
He said: "That's why I can't go... they couldn't protect me from those laws.
"Two and a half hours from London! In the land of Tchaikovsky, Diaghilev, Rudolf Nureyev - gay artists whose sexuality informed their work."
The letter can be read in full on the Independent's website.