Muslim rebels engaged in peace talks with the Philippine government say they are involved in the search for an Australian man kidnapped last month.

A spokesman for the Moro Islamic Liberation Front (MILF) says the group is working with the government to establish the location of Warren Rodwell, who was kidnapped last month on the island of Mindanao.

"We are working on it and all (the information) we gather we will feed to the ad-hoc joint action group," rebel spokesman Vol Al-Haq said.

The 53-year-old expat from Sydney was living on the island in the troubled south of the country with his Filipina wife.

He was kidnapped at gunpoint and may have been taken to the island of Basilan by smaller rebel group Abu Sayyaf.

There are unconfirmed local reports that the group has released photographs to prove he is alive and is demanding a ransom.

Philippine police have declined to comment on the reports, as has Australia's Department of Foreign Affairs and Trade (DFAT).

"It would be unhelpful to comment in detail on developments in the investigation," a DFAT spokeswoman said.

Abu Sayyaf is not part of peace talks between the MILF and the government.

The small band of Islamic militants was formed with seed money from Al Qaeda in the 1990s.



It has carried out numerous kidnappings for ransom, often targeting foreigners and Christians and a spate of high-profile bombings over the past two decades.

ABC/wires