Lawyers acting for PKR de facto leader Anwar Ibrahim have urged the authorities to remove him from jail and place him under house arrest to enable him to have access to regular medical treatment.

In a press release today, lawyer Sivarasa Rasiah and Jared Genser said Anwar's health is deteriorating rapidly because he is being denied the appropriate medical treatment.

Sivarasa and Genser said Anwar has lost 6kg since his incarceration on Feb 10 and is suffering from irregular blood pressure, a 4cm growth in his kidney, muscle tear on his shoulder and chronic arthiritis.

Among other treatments, the lawyers said, Anwar required a gluten-free diet and intensive physiotherapy, which cannot be offered in the Sungai Buloh prison.

This was deduced after Anwar was sent to the Kuala Lumpur general hospital on June 2, where he was housed for two days.

"The doctors reported to him orally that he requires further evaluation and treatment relating to a number of medical issues

"(But) the prison says it has received no medical report from the hospital requesting further testing," the statement by the lawyers says.

Anwar's confinement cell is a solitary unit, where he bathes using a bucket and uses a squat toilet. The lawyer said the hot and humid conditions, with minimal ventilation, have exacerbated his health problems.

Sivarasa and Genser's statement appears aimed at an international audience.

Genser is the head of Washington DC-based human rights group Freedom Now, an independent non-governmental organisation that works to free prisoners of conscience worldwide.