Three Federal Court judges presiding over an appeal on alleged war criminal Charles Zentai's extradition order have reserved their decision.

Last year, a Federal Court judge ruled the Australian Government had erred in agreeing to extradite Mr Zentai to Hungary.

The Commonwealth is appealing against that ruling and a two day hearing at the Federal Court in Perth finished today.

It is alleged Mr Zentai murdered a Jewish teenager in Budapest during World War Two.

Mr Zentai, who is 89, suffered a stroke last week and was not in court, however, his family and friends attended.

Yesterday, his son Ernie Steiner described what was happening to his father as inhumane.

He said the proceedings were taking a heavy toll on his father.

"I'm hoping that the appeal is dismissed and I hope that's the end of the issue," he said.

"But the Government has indicated that they will take this matter to the High Court if they lose in this full Federal Court."

Mr Steiner said other options would be better.

"They could interview my father in Australia if the Hungarians send officials out. My father's perfectly willing to answer questions, he's said that many times before," he said.

"He's got nothing to hide, and why they don't do that, it's the most logical thing; they've spent hundreds of thousands of dollars on this case and it's just pointless."

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