A Bangladesh court said on Monday the trial of detained former Prime Minister Sheikh Hasina on graft charges could continue in her absence, paving the way for her to go abroad for medical treatment.

Hasina asked the court on Sunday to allow lawyers to appear on her behalf, after a government-appointed medical board suggested she should be sent abroad immediately for treatment.

Her arch-rival and fellow former Prime Minister Begum Khaleda Zia, who is also facing corruption charges, said on Sunday she would not seek medical treatment abroad, accusing the government of setting a trap ahead of an election planned in December.

It was not clear whether the army-backed interim government would block their return if sent abroad on health grounds. An attempt to block Hasina's return from the United States early last year failed due to protests and international pressure.

Hasina is suffering from high blood pressure, eye problems and hearing impairment caused by grenade blasts at a rally in Dhaka in 2004, which killed 23 leaders and workers of her Awami League party.

Her lawyers told reporters that Special Court Judge Mohammad Feroze Alam accepted her plea and said she could be represented by lawyers at her trial.

Media reports and party officials said Hasina could be leaving shortly for Canada en route to the United States, where her children live and where she has previously been treated.

Another medical board examined Bangladesh Nationalist Party leader Khaleda and suggested she also be taken abroad for treatment for arthritis and problems in her knees.

Khaleda told a court on Sunday she would prefer to be treated in Bangladesh.

Both the former prime ministers have been in jail since last year, when they were arrested in a countrywide drive against corruption.

Khaleda's two sons, Tareque Rahman and Arafat Rahman, and dozens of former ministers are also in jail facing corruption charges. Doctors have suggested that Tareque, Khaleda's likely political heir, and Arafat should also be sent abroad for health care.

Prison officials said on Monday they were awaiting decisions from the Home (Interior) Ministry regarding sending Hasina, Khaleda and her sons abroad on parole.

Both former premiers deny any wrongdoing and say the charges are designed to prevent them contesting the election. Their parties demand they be freed unconditionally.