Hosni Mubarak's doctor said the former Egyptian president is not undergoing chemotherapy for cancer but suffers from weak muscles and limited mobility, in a rare interview published Wednesday.

"We are still running tests to ascertain that he does not have this disease (cancer). It is still not 100 percent that he has it and he has not undergone any chemical treatment," oncologist Yasser Abdel Kader told the government daily Al-Ahram.

His remarks came as Mubarak was flown by helicopter from a military hospital and wheeled into court where his trial resumed with the defence arguing its case for the second day on Wednesday.

Mubarak, who is being treated for a heart condition, has attended the court lying on a hospital bed since his trial opened on August 3 last year, except for one occasion when he sat on a chair.

"His muscles are weak, therefore limiting his mobility," said the doctor, Mubarak's personal physician before he was ousted from power last February in a popular revolt, and who was was appointed by the court to monitor his health.

Asked by Al-Ahram if mobility is dangerous for Mubarak, the doctor said: "The court asked me if, in his condition, he can sit up on a wheelchair rather than lie on a hospital bed.

"My reply was that it was not dangerous... but he does not have the ability to move a lot," he said.

He also dismissed claims that Mubarak exercises in detention, as he did before his incarceration when he was president and known to play a good game of squash.

"He cannot do that... His health is unstable," Abdel Kader said.

The doctor said he was under orders by the court not to reveal details about Mubarak's health.

"The only thing I can say is that concerning the tumours, he is stable. He had a tumour and it was removed during his medical trip to Germany," he said.

In March 2010, Mubarak went to Germany for surgery.

Doctors said at the time that he had suffered from chronic calculus cholecystitis -- an inflammation of the gall bladder accompanied by gall stones -- and a duodenal polyp.

He underwent surgery to remove his gall bladder and a polyp.

His lawyer Farid al-Deeb has repeatedly said that Mubarak suffered from cancer but officials dismissed the claims.

On Tuesday the lawyer said there is no evidence that he ordered Egyptian security forces to open fire on protesters, as they challenged prosecution calls for the ousted president to be hanged.