Dhaka - Bangladeshi former prime minister Khaleda Zia and her two sons on Thursday sought the withdrawal of graft charges brought against them.

"We have filed applications seeking withdrawal of the 21 cases," Sanaullah Mia, one of Zia's attorneys, told reporters after filing the appeal. "... These cases have no merit."

Four graft cases against the former premier; 12 against Tarique Rahman, her eldest son; and five others against Arafat Rahman, her youngest son, were filed during the two-year rule of a military-backed interim government, which detained nearly 200 politicians, including Zia and current Prime Minister Sheikh Hasina Wazed, while it was in power until early this year.

Zia, also the chief of the Bangladesh Nationalist Party, is now the opposition leader in Parliament. Her sons have been staying abroad since late 2008.

Mia said the charges brought against them were politically motivated and the High Court had earlier stayed the proceedings of all the cases.

Security forces had arrested Zia and Arafat Rahman soon after the Anti-Corruption Commission lodged the graft charges against them in September 2007. Tarique Rahman was arrested in March of the same year.

Zia was granted bail and was released from jail in September last year and her youngest son left Dhaka for Bangkok in July last year after he was paroled for medical treatment. Tarique Rahman was also undergoing medical treatment in London after his release on bail.

Soon after assuming office, Bangladesh's Awami League alliance government established a committee to review "politically motivated" charges brought during Zia's five-year and the military-backed government's two-year terms.

The committee headed by State Minister for Law, Justice and Parliamentary Affairs Quamrul Islam is to review the appeals seeking withdrawal of the allegations.

The government is to receive such applications until May 17.

As many as 3,000 such applications had been received by Wednesday from across the country, including 800 in Dhaka, from both sides of the political divide, the Bengali-language Jugantor newspaper said.

Those applications included ones also seeking the withdrawal of graft cases against Hasina, it said.