If the Malaysian government files an application in Australia to extradite Sirul Azhar Umar, his legal team will file a suit in Kuala Lumpur to challenge it.

Lawyer Kamarul Hisham Kamaruddin said this was because an application on the part of Malaysia would go against the treaty on extradition.

"If the Malaysian government files a bid to extradite Sirul, we will mount a legal challenge here.

"It will be done via a suit as this will go against the treaty (of extradition), which stipulates a person facing the death penalty cannot be extradited," Kamarul (left) said.

Last week, the Federal Court sentenced Sirul, and another former police commando Azilah Hadri, to death for the murder of Mongolian national Altantuya Shaariibuu.

The apex court also issued a warrant of arrest for Sirul.

Following this, it was reported that the law in Australia dictates that those facing the death penalty in his or her home country cannot be extradited.

Kamarul said this is on grounds of Australia having done away with the death penalty and not allowing prisoners who will be put to death in their home country to be deported from Australia.

He said he would certainly challenge if Malaysia puts in an extradition request, since Australian law prohibits surrendering a person who is subject to the death penalty in that person's home country.

Earlier reports said Sirul was in Australia and that he does not have the money to return to Malaysia.

Australian Queen's Counsel Mark Trowell told Malaysiakini last week that Sirul's issue may cause a diplomatic problem between Australia and Malaysia, if it was true the convicted murderer was there.

Meanwhile, Kamarul also noted that the Federal Court's decision had "opened a can worms".

He cited the fact that a motive was not established by the courts and highlighted the phone calls that took place right up to the night of the murder.

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