One of the two men in custody in Malawi for homosexuality offences is ill, campaigners say.

Steven Monjeza, who was arrested with Tiwonge Chimbalanga after they had a marriage ceremony in December, is said to be suffering from vomiting, chest pain and tiredness.

The pair have been held in the overcrowded Chichiri prison in Blantyre for the last four months, although they have not been convicted of any crime.

Unusually, they have been denied bail. Authorities have said this is for their own safety.

They were expected to be jailed last month but a judge delayed sentencing to allow them to defend the case.

Gay rights campaigner Peter Tatchell said he had been told Mr Monjeza has been ill for two weeks and that conditions in his shared cell were poor.

Mr Tatchell, who has not seen Mr Monjeza but has been given updates on his condition by supporters in Malawi, added: “Prison officials are unable to determine Steven’s illness. Although they are unsure, they are not doing further medical tests.

“Even if Steven had only bronchitis or pleurisy, we should be concerned. These can develop into pneumonia, which can sometimes be fatal.

“Steven’s poor health is confirmed by his partner, Tiwonge Chimbalanga, who has also expressed concern about Steven’s condition. Both men have urged that Steven receives hospital treatment as soon as possible.

“My independent sources agree. They say Mr Monjeza needs to go to hospital for a full medical examination and treatment. His health is likely to deteriorate further unless he gets medical care.”

Mr Tatchell called on people to lobby their MPs to pressure Malawi to ensure Mr Monjeza is given hospital treatment.

The pair could face up to 14 years in jail, in line with the country’s strict laws on homosexuality.

They have been in custody for almost four months, having twice been denied bail, and have pleaded not guilty to charges of sodomy and indecency.

Their supports and lawyers argue their arrest and detention is unconstitutional.