The cast and crew of the 2014 British film Pride – including Bill Nighy, Dominic West and Imelda Staunton – have issued an open letter condemning the banning of a screening of the film in Turkey, as well as the suppression of the annual Pride march.

The letter states: “As members of the creative team which produced the 2014 film Pride, and activists portrayed in that film, we are disturbed by reports of the growing repression of the LGBT+ community in Turkey culminating in the recent ban of the annual Pride parade and police violence against those who courageously defied the ban.

“Reports that the Ankara authorities also banned a screening of the film Pride are a chilling reminder that political authoritarianism regards artistic expression as its enemy.”

The Pride march has been officially banned for the past three years, and an attempt by approximately 40 activists to stage one on 25 June in Istanbul’s Taksim Square was broken up by police. A screening of the film Pride was due to take place in Ankara on 28 June but, according to Hürriyet Daily News, the Ankara governor’s office refused to allow it go ahead, citing Turkey’s current state of emergency and arguing that it could “incite hatred and enmity”.

The open letter from the cast and crew continues: “We send our unshakeable solidarity and support to LGBT+ people in Turkey who are now challenging the ban on LGBT+ events in Turkey. We deplore the decision of the Ankara Governate in banning the screening of Pride, and call on the ambassador for Turkey in London, Abdurrahman Bilgiç, and the UK foreign secretary Boris Johnson, to condemn the repressive actions of the Turkish authorities.”

The film’s director, Matthew Warchus, writer, Stephen Beresford, and actor Andrew Scott are also among the signatories.