Australia has accused the Bulgarian Government of verballing Canberra's top representative to the region in a formal statement on Jock Palfreeman's extraordinary detention in Sofia, raising diplomatic tensions between the two countries to a new high.

Key points: Jon Philp's reported comments represent a reversal from Marise Payne's position only six days ago

Jon Philp's reported comments represent a reversal from Marise Payne's position only six days ago Jock Palfreeman says if the statement is true, it is a "major betrayal by Australia"

Jock Palfreeman says if the statement is true, it is a "major betrayal by Australia" Palfreeman has spent 19 days in the Busmantsi Detention Centre in Sofia after being granted parole

The stoush comes after Bulgaria's Foreign Minister announced in late September she had refused Australian Foreign Minister Marise Payne's request for a formal meeting on the Palfreeman case when both were in New York for a United Nations summit.

The latest statement, from Bulgaria's Justice Minister, Danail Kirilov, quoted Australia's Charge d'Affaires, Jon Philp, as having said: "Australia is aware that currently everything is proceeding according to Bulgarian law and there are no deviations in the judiciary process."

Issued after meetings between the two, Mr Kirilov's press release prompted Mr Palfreeman himself to describe the statement — if true — as a "major betrayal".

Mr Palfreeman has been detained for 20 days in a Sofia immigration facility, even though under Bulgarian law he is considered a free man.

Despite being granted parole, a highly irregular legal appeal by Bulgaria's prosecutor-general has ensured he remains in custody.

His parole, and the Government's heavy-handed response, has ignited a political storm in Bulgaria. Hundreds of judges have protested against the Government's response to the case.

Now, the Department of Foreign Affairs and Trade (DFAT) has accused Bulgaria of misrepresenting what was said in the top-level meeting on Tuesday.

"Mr Philp explicitly did not use the words that he has been quoted as using," a spokesman for DFAT said.

"He also expressed a range of concerns, including pointing to a risk that outside pressure might influence the outcome, which as previously stated would be of significant concern to Australia.

"Importantly, he raised Australia's concerns that the legal basis for Mr Palfreeman's continued detention remains unclear and that, consistent with parole being granted, he should be released and allowed to return to Australia."

A defaced poster supporting Jock Palfreeman on a street in Sofia. ( ABC News: Damian Vodenitcharov )

The DFAT statement also said Mr Philp, "reiterated Australia's strong position that we would be concerned if factors other than legal considerations were influencing Mr Palfreeman's case".

This statement reflects what Senator Payne said publicly last week.

Mr Palfreeman has served more than 11 years of a 20-year sentence over the stabbing death of a local student, whose father is an influential former member of parliament.

The 32-year-old has always maintained his innocence. His lawyer recently released CCTV of the night of the incident in 2007, which Mr Palfreeman said was evidence he was innocent of the murder charge of which he was convicted in 2009.

He was paroled by the Sofia Court of Appeal. Under Bulgarian law, such a decision cannot be further reviewed.

But days after it was handed down, Bulgarian prosecutor general Sotir Tsatsarov announced he was lodging an application for the Palfreeman case to be reopened and the Australian returned to jail.

The application is unprecedented and has alarmed legal experts in Sofia. It came at the same time as an investigation was opened into the appeals court judges who ruled in Mr Palfreeman's favour.

An open letter signed by 292 Bulgarian judges said the highly irregular case was, "destroying fundamental pillars of country governed by the law — the rule of law and the independence of the judiciary".

The Bulgarian Judges Union said local judges were being issued with a, "clear and categorical sign that if they don't rule in accordance with the public opinion and wills of the political parties and their specific political leaders, they are going to be abused, vilified, physically persecuted and maltreated".

Three judges of the Supreme Court of Cassation heard Mr Tsatsarov's application on Monday and then adjourned for as many as eight weeks to return a decision.

The new statement by the Bulgarian Justice Minister came after a top-level meeting at the ministry in Sofia, requested by Mr Philp.

The statement also said Mr Philp told Mr Kirilov that although a passport had already been issued for the Australian, the document would be withheld from Mr Palfreeman until after the completion of the latest appeal.

Mr Palfreeman told the ABC he had yet to be visited by the ranking diplomat.