Bangladesh's Supreme Court on Monday halted the release of opposition leader Khaleda Zia on bail, deepening a political crisis ahead of a national election due in December.

The top justices suspended a lower court's decision to grant Zia bail until May, prompting a sharp reaction from her lawyers who said it was part of a campaign by Prime Minister Sheikh Hasina to silence the opposition.

“It is an unprecedented order in the judicial history of Bangladesh. We think it is not the decision of the top court, rather it is a government decision,” one of Zia's lawyers, Sanaullah Mia, told AFP.

Fakhrul Islam Alamgir, secretary general of Zia's Bangladesh Nationalist Party (BNP) said the order was a “reflection” of the government's desire to keep Zia confined during the election, which is widely expected to be held in December.

“We've repeatedly said people are not getting justice in the country and the judiciary is controlled by the government,” Alamgir told AFP.

The 72-year-old BNP leader was jailed for five years last month on charges of embezzling money intended for an orphanage.

The three times former prime minister, now being held in a special jail, has consistently dismissed the charges as politically motivated.

The BNP wanted Zia freed pending appeals before a high court so that she can lead the party's election campaign.

Violence erupted in cities across Bangladesh after the guilty verdict on February 8 as BNP supporters clashed with police and ruling party activists.

Zia, who entered politics in the 1980s after her military dictator husband was assassinated in a failed coup, also faces dozens of separate charges related to violence and corruption.

Her party boycotted a 2014 national election in which Hasina was re-elected. The BNP is expected to contest the upcoming election however.

Zia and her son were detained by an army-backed government in 2007 and spent a year and a half in detention pending trials for alleged corruption.