A Bangladeshi professor convicted after allegedly wishing death on the prime minister in a Facebook update said Monday he feared for his life if he returned to his country from his adopted home in Australia.

Bangladesh's High Court last week convicted Ruhul Khandaker in absentia and sentenced him to six months in jail for contempt of court after he failed to respond to summonses to explain his posting.

He will also be prosecuted for sedition and the court has asked the foreign ministry to bring the 29-year-old from state-run Jahangirnagar University back to the country so he can face charges.

Khandaker, who has been doing PhD research since 2009 at Curtin University in Perth, western Australia, questioned in a Facebook posting in August why the government gave driving licences to unqualified drivers.

"Many die, why does not Sheikh Hasina die?" court documents quote the posting as saying, referring to the prime minister.

He was apparently upset after a road accident that killed Bangladesh's famous filmmaker, Tareq Masud.

The Facebook posting first came to light in a report in a local newspaper in August, prompting the high court to seek an explanation from the lecturer.

In an email exchange with AFP, Khandaker said that "in the current situation I'm really worried of safety of my life" and that he was seeking "safety and security" from the Australian government.

"If I'm forced to go back to Bangladesh now, my life could be threatened and possibly even get killed," he wrote.

"I was doing well in my research, but now my life is threatened by a political incident even though I had no involvement in any type of politics," he said.

"I want to survive first and don't want to return (to) Bangladesh at the moment."

Bangladesh does not have an extradition treaty with Australia, a foreign ministry source told AFP.

Khandaker also denied wishing death on the prime minister.

"I strongly say that I did not wish the prime minister's death by the Facebook status, or I didn't have any such intention," he said in a six-page statement to AFP.

The comment which landed him in trouble was posted from Australia and has since been deleted.

The case is the first time a Bangladeshi has been sentenced to jail and is being tried for sedition for making comments on a social networking site.