An Australian doctor now working for Islamic State in Syria says Australia has blood on its hands and he never intends to return.

Doctor Tareq Kamleh has worked in several Australian hospitals in Queensland, South Australia and the Northern Territory and is registered as a doctor in Western Australia.

Last month, the former paediatric registrar appeared in an IS propaganda video revealing he had travelled to Syria to work for the terrorist organisation.

He urged other Australian medical professionals to do likewise.

Earlier this month, the Australian Health Practitioner Regulation Agency (AHPRA) announced that the Medical Board of Australia had begun regulatory action in relation to Dr Kamleh's medical registration.

Dr Kamleh has since posted a letter of response to AHPRA on his Facebook page, denying he had ever taken part in unprofessional action that would have jeopardised his doctor-patient relationships.

"I made a very well educated and calculated decision to come here, it did not involve any brainwashing," he said in the letter.

"Since being here I have seen that it is in no way as described by the colourful Australian politicians 'murdering and raping everyone in their way' ... 'death cult'.

"The only death that I have had to deal with since being here has been from either pathology or coalition drone strikes.

"Interestingly the two drone strikes that have occurred since I have been here have not claimed the life of a single male, let alone a soldier ... good work 'Team Australia'! ... from what I've seen you have more blood on your hands than ISIS has on their knives.

"I never intend to return to Australia, I have finally returned home."

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Dr Kamleh signed the letter in two names — he assumed the name Abu Yousef Al-Australie upon arrival in Syria.

"I have come here as there are locals suffering from normal medical conditions despite being surrounded by war, with an overt lack of qualified medical care," he said.

"Is it not my humanitarian duty to help these children also?! ... or only kids with white skin and blue passports?

"I have no input or responsibility over the political or military actions of the state, if they are correct I wish them progression, if they are not, this is between them and God."