Dhaka, April 22: New US Ambassador to Bangladesh James F. Moriarty has urged that emergency be lifted to ensure credible elections in the country.

He said that it would be "extremely difficult" to conduct polls under emergency rules in force since January last year.

The emergency "does not allow political parties to campaign for elections and hinders other electoral preparations", Moriarty said at a media meet Monday after presenting his credentials.

The new envoy said that former prime ministers Khaleda Zia and Sheikh Hasina "should be released if the allegations against them are insubstantial".

He hoped that due process would be followed and fair, free and transparent trials would be held "as soon as possible if there are substantial allegations", the United News of Bangladesh (UNB) news agency reported.

"If there are signs that the trials are not transparent, free or fair, that will undermine efforts to re-establish democracy," he said.

The US, Moriarty said, was encouraged, by assurances from the caretaker government, which has been in office for the last 15 months, about the army's limited role in governance.

"I will tell the government... that the US believes credible elections would be extremely difficult under a state of emergency and it should be lifted.

"My hope is that those elections will result in a more stable and deeply rooted democracy," said Moriarty, who was last posted in Nepal.

"This is a critical time for Bangladesh, a country in transition in a region of the world vital to US interests."

The envoy added: "Promoting democracy, ensuring development and denying space to terrorism are the key challenges Bangladesh faces, and are vital to the future of the relationship between our countries."