Ken Loach, Mike Leigh and others call for release of Ukrainian director

Some of the most highly-regarded film directors in Europe, including Pedro Almodóvar, Ken Loach, Béla Tarr and Wim Wenders, have co-signed a letter to Russian authorities who are currently detaining a Ukrainian film-maker, Oleg Sentsov.

Sentsov was arrested in May at his home in Simferopol, Crimea, charged with attempting to organise a terrorist attack, and Russia's Federal Security Service has said he has admitted to plotting attacks on railway bridges, power lines and public monuments. His lawyer Dmitry Dinze, a veteran of the Pussy Riot trial, has however said Sentsov denies any involvement. The head of a German film fund who supported his movies, Kristen Niehuus, claimed that Sentsov was merely a protestor against the annexation of Crimea by Russia.

The European Film Board, chaired by Agnieszka Holland, are now writing to Vladimir Putin and others to ask him "to ensure the safety of Oleg Sentsov; to make public the whereabouts of the detained; to have the detained charged with a recognisable offence or released; to instigate a full, prompt and impartial investigation into the apparently arbitrary detention by the FSB in order to bring all those responsible to justice." The letter adds that the film-makers are "deeply worried and cannot stop wondering how he is and what his future will be." Other British names adding their support to the letter are directors Stephen Daldry and Mike Leigh along with producers Mike Downey and Rebecca O'Brien.

Sentsov's debut feature Gaamer, about a video game tournament, was highly regarded on the eastern European festival circuit, and helped secure him funding for a forthcoming feature Rhino, production on which was postponed by his work with the protest movement.

A Russia-funded film about the Crimean conflict is meanwhile being developed, which the filmmakers say will "focus primarily on the human angle", rather than the political theatre around the unrest.