Australian anti-Islamic State fighter Ashley Dyball has had his passport cancelled again, despite never being charged over the time he spent with a Kurdish militia fighting against IS in Syria.

Key points: Mr Dyball was detained at Brisbane airport last week

Mr Dyball was detained at Brisbane airport last week He had a one-way ticket to Sweden

He had a one-way ticket to Sweden Mr Dyball has still not been charged over the time he spent in Syria

Mr Dyball has been in limbo since being deported from Germany to Australia in December, after German officials detained him while he was taking a break from the battlefield in Syria.

His passport was cancelled when he arrived home.

Although he was investigated by the Australian Federal Police on suspicion of engaging in hostile activities against a foreign government, Mr Dyball has still not been charged.

Mr Dyball's passport was returned to him earlier this year to enable him to travel to Fiji for a family holiday, but he was detained at Brisbane airport last week in possession of a one-way ticket to Sweden, and was told his passport had been cancelled again. He declined to comment on Friday.

Despite the Australian Government's public position that any Australian citizen travelling to the Middle East to fight against Islamic State, or even preparing to do so, could be breaking the law, only one such person has been charged.

Melbourne man Jamie Williams was charged with breaking the "foreign incursions" law after making preparations to travel to Syria, but the charges were later dropped.

Commonwealth Attorney-General George Brandis made the decision to drop the charges against Mr Williams, but refused to explain his reasons.

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Mr Williams' lawyers argued that the YPG, the militia Mr Dyball served with and which Mr Williams was attempting to join, is the de facto government of parts of northern Syria, and therefore any Australian joining it was not breaking the law.

There are growing calls for Australians who travel to the Middle East to fight against Islamic State to be distinguished in some way from Australians who join the Islamic extremist group.

The cancellation of Mr Dyball's passport comes as he and other sympathisers with the Kurdish cause prepare to commemorate the first anniversary of the death of Queensland man Reece Harding, who was killed fighting with the YPG against Islamic State.

The 23-year-old's parents, Michele and Keith Harding, who have become vocal advocates for the Kurdish cause since their son's death, organised a ceremony at a Gold Coast chapel to mark the anniversary.