A British father battling cancer is barred from leaving the United Arab Emirates after he was arrested for allegedly having "too many" anti-anxiety pills.

Perry Coppins, a 61-year-old maritime security officer from Nottingham, reportedly told authorities he needed enough tablets to last him during a six-month voyage at sea.

Coppins is said to have been arrested in November during a luggage check at the port of Fujairah, east of Dubai, when his prescription paper work was denied.

The father-of-three was reportedly jailed for five weeks before his first court appearance and was denied medicine while in jail as his psychological condition deteriorated, The Mirror reported.

Justice group Detained in Dubai, which is based in London, said Coppins has been bailed from jail but remains in Dubai after his passport was confiscated. The group's chief executive, Radha Stirling, claims Coppins was diagnosed with prostate cancer since the arrest but is being denied medication and treatment.

Coppins has allegedly lost 20kg and is suffering from hallucinations, pain, stress and blindness, Stirling said. She added that he is at risk of becoming homeless after losing his job and being unable to work. Coppins will have to wait up to 18 months for the court process to finish.

"Because he has not had the treatment he needs, he now needs an operation to save his life," she said. "This is also being denied by the UAE authorities."

The group said Coppins had been taking Temazepam, Clonazepam and Citalopram prescribed by his GP for the past 21 years.

When asked about Coppins' case, a Foreign & Commonwealth Office spokesman said: "We have been providing consular assistance to a British man following his arrest in Dubai in November and are in contact with the Dubai authorities."

Coppins is father to 10-year-old Mia, 21-year-old Cameron and 24-year-old Pia, who are all back home in the UK.

In a statement released by Detained in Dubai, Pia said: "It's so cruel. Nobody should be treated like this.

"He is not a young man and he needs medical help to cope with his anxiety. Not being allowed his cancer treatment is like giving him a death sentence. Does human life mean nothing to those people?"

Coppins' ex-wife Lesley added: "Perry and I split up, but he is a good man who loves his kids. I really hope the Dubai authorities decide to do the humane thing and let him free."

Stirling noted that Coppins' medications are all legal in the UAE "provided the patient has prescription documentation, which Perry has.

"The initial mistake of the customs officer should never have escalated into criminal charges; but this reveals the lack of cohesion within the legal system, and what appears to be the capriciousness of the Public Prosecutor's office.

"Perry needs urgent treatment for his prostate cancer. To deny him this in a timely fashion is an absolute violation of his human rights.

"We hope that the UAE will show compassion to Perry and his children, and release him immediately, so that he can return home for the medical treatment he needs."