The Australian Foreign affairs officials say they saw no reason to keep Sri Lankan High Commissioner to Australia Admiral (Retd) Thisara Samarasinghe from taking up his posting.

The Australian Greens and Tamil groups want Thisara Samarasinghe recalled or expelled over unproven claims he is responsible for war crimes, states the AustraliaNews.

The Australian Department of Foreign Affairs and Trade (DFAT) Secretary Dennis Richardson said his department advised Foreign Minister Kevin Rudd to approve Admiral Samarasinghe's appointment earlier this year, despite the opposition of Tamil groups.

"We saw no reason for him to be denied agreement," Mr Richardson told a Senate estimates committee in Canberra on Thursday.

DFAT provided its initial advice on February 10. Mr Rudd approved the appointment on April 2.

Mr Richardson also defended Australia's High Commissioner to Colombo Kathy Klugman, who praised the Sri Lankan navy for intercepting a people smuggling boat last month, the AustraliaNews further states.

In an interview with the Queanbeyan Age, Sri Lankan High Commissioner also cast himself as a uniter of the Sinhalese and Tamil communities in Australia, claiming he devoted as much time and attention in his role to the two groups.