Prosecutor-General Sotir Tsatsarov on Tuesday petitioned Bulgaria’s Supreme Court of Cassation to suspend Palfreeman’s parole and review the panel’s ruling.
Palfreeman’s lawyer, Kalin Angelov, called the prosecutor’s appeal “absurd”, and advised Australian authorities to speed up the passport and put Palfreeman on a plane home.
Australia’s Department of Foreign Affairs and Trade would only say it is continuing to provide consular assistance to Palfreeman and his family.
“Owing to our privacy obligations we will not provide further comment,” a statement from DFAT said.
Palfreeman has consistently maintained he acted in self-defence when he intervened to prevent law student Andrei Monov, 23, and a group of friends from attacking two Roma, or gypsy, men.
Interior Minister Mladen Marinov on Sunday defended the decision to release Palfreeman.
“When there is deprivation of life, then there is no complete justice, there is no way to return things,” Mr Marinov told Nova TV.
“The logic of the law is to find justice and make it quick, have an effective sentence.”