(AFP) Malaysian Prime Minister Mahathir Mohamad accused his imprisoned former deputy Anwar Ibrahim on Tuesday of lying about his medical condition to win political support.

Mahathir said Anwar, who has been in Kuala Lumpur Hospital (KLH) since November with a slipped disc, does not need an operation overseas because Malaysia has the necessary specialists and equipment.

"So there's no need to say that Malaysia cannot do it. It's a lie, it's politics, just like the other day when he accused us of giving him poison, it's all lies," he told reporters.

Mahathir said the government decision not to let Anwar be treated overseas was final but that did not mean it had no sympathy for him.

"Doctors here feel that he can be treated in the country so why would he want to go overseas? Why does he want to be so privileged when he is a prisoner?" Bernama news agency quoted him as saying.

Anwar is due to announce Wednesday whether he will accept an offer of spinal surgery at his current hospital.

If he declines, he will be sent back to jail, where he is serving sentences totalling 15 years on what he calls trumped-up charges.

His wife Wan Azizah Wan Ismail was reported as saying he would probably choose to return to jail.

The government says an overseas specialist can bring in equipment and operate in Malaysia if desired. It has rejected appeals from his family that he receive surgery in a specialist German spinal clinic.

Mahathir also took issue with comments by Anwar's Dutch spinal specialist Dr Thomas Hoogland, saying he had criticised the local hospital facilities.

Ball game

Ministers last Friday briefed diplomats on the long-running controversy to counter what they called false reporting.

Health Minister Chua Jui Meng told them Anwar "received the best, the most extensive, the most unprecedented treatment for a slipped disc in the entire history of medical services in this country."

Mahathir was answering a question about an appeal by more than 100 Malaysians that the politician be allowed treatment overseas.

Anwar blames his back condition partly on a 1998 assault by the then police chief Rahim Noor. A hospital consultant has said he hurt his back during a ball game inside the jail in 1999.

Rahim was Monday sent to jail for two months for the assault. Anwar himself is due in court May 12 to hear whether state prosecutors will proceed with five outstanding charges against him.

He has already been convicted in separate trials of abuse of power and sodomy but says he was framed to remove a political threat to Mahathir - an allegation denied by the government.

During one of the trials his lawyer Karpal Singh alleged that there was a possible plot to poison Anwar with arsenic. Medical tests did not substantiate the claim. Karpal is due to go on trial for sedition next Tuesday for making the claim.