Mr Palfreeman, who appeared at the Sofia Supreme Administrative Court on Tuesday with his lawyer Kalin Angelov, said the government maintained it was unaware he had been released.

But the prosecutor's office, which hadn't until then been involved in the matter, said it wasn't its responsibility to allow the 33-year-old Australian to return home.

"The government has been officially exposed as being corrupt," Mr Palfreeman told AAP on Wednesday.

"It's just embarrassing that their lie was renounced by the representative of the prosecutor themselves.

"The government is claiming I am still in prison."

Mr Palfreeman was released on parole last September after serving nearly 12 years behind bars in the Balkan nation's capital.

The Sydney man was found guilty of murder and attempted murder for stabbing two Bulgarian youths during a street melee in 2007. He has always maintained he acted in self-defence.

He spent one month in immigration detention after his release from prison and since then has been able to walk freely around Bulgaria - subject to COVID-19 restrictions this year.

A bid to appeal his parole was thrown out of Bulgaria's highest court in May, but he remains unable to leave the country.

Last month a European Parliament committee included his case on a list of questions to the Bulgarian government.

The Democracy, Rule of Law and Fundamental Rights Monitoring Group said Bulgaria's Supreme Court of Cassation dismissed the appeal against Mr Palfreeman's parole on account of it being "procedurally inadmissible".

"Yet this Australian citizen continues to be unable to leave the country, under an order from the Ministry of Interior," it said.

"Could you explain why the court is being ignored and, if there are no proceedings against this individual, what is the basis for his ongoing detention in the country?"

A Department of Foreign Affairs and Trade spokeswoman previously said Australia had provided everything required to help Mr Palfreeman leave Bulgaria, when local authorities allow it.

His hearing at the Sofia Supreme Administrative Court continues.

Australian Associated Press