An Australian official has visited northern Syria to discuss what to do with Australian citizens who were members of the Islamic State group (IS) and their children.

Key points: Mr Philp said Australia favoured an international response to dealing with former IS foreign fighters and their children

Mr Philp said Australia favoured an international response to dealing with former IS foreign fighters and their children Dozens of Australians remain in detention in northern Syria

Dozens of Australians remain in detention in northern Syria Mr Philp did not say whether his visit was to discuss the Australians' repatriation

Kurdish authorities in north-eastern Syria said they hosted Australian foreign affairs official Jon Philp, who told local media Australia favoured an international response to resolve the cases of the 8,000 foreign women and children and 1,000 alleged foreign fighters held in the region.

"All the foreign fighters, all the foreign fighters' families who are still in the camps, no one country can think just of theirs," Mr Philp said.

"There needs to be some solution for the whole of the self-administered region to ensure that the camps don't stay here forever in this intractable and difficult way."

Dozens of Australians remain in detention in northern Syria, but Mr Philp did not say whether his visit was to discuss their repatriation, especially the orphaned children of Australian terrorist Khaled Sharrouf.

"Every family is important," he said.

"We need to deal with every family and assist the self-administering region dealing with each one."

Khaled Sharrouf's surviving children Hoda, Zaynab and Hamzeh, with two of their children, were reunited with their grandmother Karen Nettleton. ( ABC News: David Maguire )

A Kurdish-dominated coalition led the fight against Islamic State but now the Kurds are struggling to deal with the members of the group who surrendered and their families.

The Kurdish regional administration, known as the Democratic Autonomous Administration of North and East Syria (DAA), is not internationally recognised, but its cooperation is crucial to repatriating foreign citizens.

Abdulkarim Omar, the joint head of foreign relations for the DAA, said relations with Australia were positive.

"Australia is a big country and a partner in [the] international coalition fighting terrorism with us, it has played such an important role fighting terror and the official visit is an important one from the representative of Australian foreign affairs," he said.

Other countries that have sent delegations to the Kurds, such as France and Sweden, have repatriated some of their citizens, especially children.

Aid groups are warning about the dire conditions for the families held in camps in north-eastern Syria, and Kurdish authorities told the ABC 300 children had died there since March.

Mr Omar indicated the DAA was looking to prosecute IS members in Syria.

"These criminals have committed massacres in this area and they've been arrested here in this area," he said.

"We have all the evidence, we have all the information and we have eyewitnesses to prove that."