Volunteers from the Greek charity Euro Relief have been accused of trying to convert Muslims in Moria detention camp as the refugees wait to be returned to Turkey from Europe.

The Guardian reported that twice in the last few months aid workers had given out Arabic versions of the St John's gospel containing forms asking Muslim refugees to convert.

The documents ask the reader to sign a statement declaring their conversion to Christianity. "I know I'm a sinner... I ask Jesus to forgive my sins and grant me eternal life. My desire is to love and obey his word," the forms state.

Muslim asylum seekers in the camps have found the approaches insensitive, according to the newspaper.

"It's a big problem because a lot of the people are Muslim and they have a problem with changing their religion," Mohamed, a detainee from Damascus, told the paper. "They were trying this during Ramadan, the holiest Muslim month."

Two workers from Euro Relief have been identified as distributing the materials. The charity said it did not approve the distribution of the materials and could not rule out the possibility that aid workers had given out the literature through their own initiative.

"I have already taken action, so that our volunteers know very well that they should not distribute any kind of literature. Our code of conduct ... says clearly that this is something they simply cannot do and if somebody does we are going as an organisation [to] take disciplinary actions," Euro Relief's director, Stefanos Samiotakis, said.