There are growing calls for the Royal Commission into Institutional Responses to Child Sex Abuse to widen its inquiry to include alleged abuse of asylum seekers on Nauru.

Key points: Three groups wrote to commission chairman last year about including Nauru claims

Three groups wrote to commission chairman last year about including Nauru claims Thousand of Nauru abuse allegations were published this week

Thousand of Nauru abuse allegations were published this week Human Rights Commission president supports proposal

Three non-government organisations have revealed they sent legal advice to the commission that it could examine incidents of abuse at the detention centre.

"In a nutshell, the advice says that while the royal commission can't obviously go to Nauru and exercise coercive powers on Nauru, it can look at the response of the Australian Government and its contractors to child sexual abuse that occurred on Australia's detention centre on Nauru," Hugh de Kretser from the Human Rights Law Centre said.

"There has to be a connection to Australia — that connection is established by the level of control, financing and involvement that Australia and its contractors have over the institution that we have set up as a detention centre on Nauru."

The Human Rights Law Centre, the Council for International Development, and the Australian Council of Social Service sent legal advice on the matter to the chairman of the royal commission Justice Peter McClellan in July last year.

Mr de Kretser said the move was being revealed today in the wake of The Guardian publishing thousands of files detailing allegations of abuse on Nauru.

"We've taken the step to make this advice public on the back of the widespread evidence of ongoing harm to innocent people, including children, that was revealed this week through the leaked files — the over 2,000 incident reports showing ongoing child abuse, ongoing sexual abuse, ongoing harm self-harm suicide, assaults and injuries," he said.

"You've got a situation where the royal commission is doing fantastic work in Australia to prevent child sexual abuse — at the very same time the Australian Government is warehousing kids offshore in conditions where that abuse thrives.

"It has to stop."

Marc Purcell from the Council for International Development urged the commission to accept the legal advice.

"There is Commonwealth responsibility for the harm being caused to people on Nauru and children," he said.

"It would be problematic and indeed seem strange to the average member of the public if the royal commission, which is looking at historical examples of abuse — some that have come right up into the 2000s, did not consider these very, very recent examples over the last three years of how the Commonwealth as an institution has sought to respond and indeed deal with harm that has come to children under their care in the Nauruan detention centre."

Human Rights Commission backs move

Gillian Triggs, the president of the Human Rights Commission, told Radio National the royal commission should be extended.

"I think that a royal commission could investigate, in my view, matters for which Australia … have managed and paid for the entire process," she said.

"It is not good enough to say that this is for another sovereign nation."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 6 minutes 50 seconds 6 m Peter Dutton discusses the leaked Nauru files ( Leigh Sales )

Immigration Minister Peter Dutton told 7.30 on Thursday that it was up to Nauru to investigate the cases revealed by The Guardian.

"Nauru is not part of Australia so this is an issue for the Nauruan Government," he said.

When pressed on the point Australia was paying $1.2 million a year to run the facilities, Mr Dutton said: "This Labor legacy is going to last along time. We are not going to clean up this mess that Labor created overnight."