Prison Break star Wentworth Miller has published a strongly worded letter declining an invitation to attend a Russian film festival in light of the country’s new anti-gay laws.

The actor, 41, who confirmed that he is gay publicly for the first time via the letter, turned down an offer to be a “guest of honour” at the St. Petersburg International Film Festival.

He wrote: "Thank you for your kind invitation. As someone who has enjoyed visiting Russia in the past and can also claim a degree of Russian ancestry, it would make me happy to say yes. However, as a gay man, I must decline."

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"The situation is in no way acceptable," he wrote, adding: "I cannot in good conscience participate in a celebratory occasion hosted by a country where people like myself are being systematically denied their basic right to live and love openly."

Miller stated that he was "deeply troubled by the current attitude toward and treatment of gay men and women by the Russian government.”

The letter, addressed to festival director Maria Averbakh, was published on the website of advocacy group GLAAD - formerly known as the Gay & Lesbian Alliance Against Defamation.

Miller, who played Michael Scofield in the Fox network’s Prison Break from 2005 to 2009, has recently become a screenwriter. Recent writing credits include Stoker, which stars Nicole Kidman and Mia Wasikowska.

He is just the latest acting luminary to add his voice to the growing dissent regarding Moscow’s newly adopted homophobic laws.

Russian President Vladimir Putin signed an act banning the “propaganda of non-traditional sexual relations” in June. The laws impose heavy fines on anyone organising a gay pride event or providing information about homosexuality to people under 18.

Writer and broadcaster Stephen Fry has since called for a boycott of the 2014 Winter Olympic Games, due to be held in Sochi, Russia in February.

Actor Rupert Everett also added his voice to the dissent, telling The Independent last week: “If you are gay in Russia you don’t know anything about anything. You have no idea Aids exists because there’s no information. You live very secretly. If anyone finds out… you are liable to be beaten up, or killed, or forced to commit suicide.”

Bravo channel host and executive producer Andy Cohen told E! News last week that he would not be co-hosting Donald Trump's Miss Universe pageant this year in Moscow because he "didn't feel right as a gay man stepping foot into Russia."

Homosexuality was decriminalised in Russia in 1993. The new laws have been vocally criticised by human rights groups and politicians in the West.