A major European security organisation has come under fire over the “mind-blowing” decision to host a highly controversial Muslim group whose former director praised the Isis murderer “Jihadi John”.

The Organisation for Security and Cooperation in Europe (OSCE) invited advocacy outfit Cage — formerly Cageprisoners — to speak at its Warsaw Human Dimension Conference last week.

Cage’s managing director, Muhammad Rabbani, spoke at the event to condemn an “Islamophobic, state-led programme of repression” that he claimed had been launched by the French state.

Cage gained public prominence in 2015 after its research director, Asim Qureshi, described Isis killer “Jihadi John” as a “beautiful young man”.

Speaking at a press conference he said: “He was the most humble young person that I knew. This is the kind of person that we are talking about.”

In 2013, the Community Security Trust raised concerns over “antisemitic” material on Cage’s website. The now-deleted article implied that the Jewish owner of the World Trade Center, Larry Silverstein, was involved in a conspiracy to destroy the twin towers in order to claim insurance.

The OSCE is the world’s largest regional security-orientated intergovernmental organisation and holds observer status at the United Nations.

Discussing Cage ’s invitation to speak at the conference, a spokesperson for Muslims Against Antisemitism said: “The OSCE is funded by the taxpayers of European nation states and beyond. The fact that European taxpayer resources have been used to invite and host Cage is truly mind-blowing.

“Furthermore Cage’s work pitting Muslim communities against the British and French governments, as though these governments seek to undermine Muslims, is extremely troubling.”

Cage has been contacted for comment.