Dhaka: In a move that could ultimately help Bangladesh's army-backed government achieve credible elections, former Prime Minister Shaikh Hasina left Dhaka on Thursday  for foreign medical treatment.

Hasina's Awami League, one of the country's top political parties, has been at loggerheads with the self-defined "interim authorities" over her detention on graft charges, and reluctant to commit to participating in a parliamentary election set for December.

But that has changed now that Hasina has been allowed to fly to the United States for medical treatment on an 8-week parole.

Before leaving, she briefly met senior leaders of the Awami League at the airport.

"We assured her of the party's unity," Syed Ashraful Islam, general secretary of Awami League, told reporters. He said Hasina also asked them to prepare for the December election.

Political analysts said Hasina's freedom, temporary though it may be, had moved the Awami League and government towards a "win-win situation" that would push the political process forward.

"People would now hope the government might offer a similar olive branch to Hasina's rival Begum Khalida Zia and release her from detention," said Professor Ataur Rahman Khan, president of the Bangladesh Political Science Association.

Khalida heads another leading group, the Bangladesh Nationalist Party (BNP), whose participation the government also needs to convince foreign governments the December poll is a legitimate one. Like Hasina, she faces graft charges. "The government is trying to [say] that the judicial process and politics can continue side by side, and the parties may buy it in good faith," Ataur told Reuters yesterday.