The European Union says Turkey must respect the "presumption of innocence" principle in its prosecution of a businessman and activist accused of attempting to overthrow the government.

Osman Kavala was detained last month for alleged connections to U.S.-based cleric Fethullah Gulen, whom Turkey blames for a failed military coup last year. Kavala was charged with crimes against the state this week.

Turkish President Recep Tayyip Erdogan has called Kavala "Turkey's Soros," a reference to American billionaire George Soros.

Soros' Open Society Foundations have funded education, health, justice and media projects around the world.

Pro-government media in Turkey accuse Kavala of engaging in anti-government conspiracies.

EU spokeswoman Maja Kocijancic said Friday that the public rhetoric about Kavala "cast serious doubt on the respect of due process and the presumption of innocence."