His move came as former prime minister Kevin Rudd said he backed calls for a royal commission on child sexual abuse within the Catholic Church if state inquiries required bolstering.

Prime Minister Julia Gillard is considering calls for a federal inquiry but declined today to respond to the growing clamour for action as cabinet minister Penny Wong said any inquiry should be “full, frank and fearless”.

Mr Abbott said the coalition ‘‘would be prepared to support’’ a wide-ranging royal commission investigation into the sexual abuse of children providing it was both proposed by the government and was not limited to one institution .

''It's clear that for a long period there was insufficient awareness and insufficient vigilance when it came to predatory behaviour by people in positions of authority over children,’’ he said in a statement on Monday.

''A lot of terrible things have been done, and a lot of people have suffered deeply.

''For these reasons, if the government were to propose a royal commission to investigate the sexual abuse of children, it is something the coalition would be prepared to support.’’

Mr Rudd said a nationwide royal commission must be considered regardless of current state inquiries in NSW, Queensland and Victoria. Mr Abbott said any commission should inquire beyond the Catholic Church.

Mr Rudd said in a statement: ‘‘Like many Australians I have been deeply disturbed by recent statements by Detective Chief Inspector Peter Fox of the NSW Police and by Deputy Police Commissioner Graham Ashton of the Victorian Police concerning institutional resistance to investigations of cases of child abuse.

‘‘Any form of child abuse is intolerable at any time and under any circumstance.’’

Mr Rudd said he supported the Carmody Commission of inquiry, currently underway in Queensland, investigating that state’s child protection sytstem.

He also backed the decision by NSW Premier Bary O’Farrell to convene a special commission to investigate allegations of abuse by Catholic clergy in the Hunter region, and a current Victorian parliamentary inquiry into the handling of child abuse by the Church.

But Mr Rudd said these may not be enough.

‘‘If either of these independent inquiries conclude that there is evidence of institutional resistance on the part of the Catholic Church or that more resources are needed to deal with these matters, then I believe this would constitute a clear case for a national Royal Commission,’’ he said.

‘‘Under any such Royal Commission, there should be an open examination of what has occurred in the past; what further reforms are necessary for the future as well as addressing the key question of appropriate compensation for victims.’’

He said other institutions, apart from the Catholic church, should be looked at it warranted.

‘‘Consideration should also be given to other institutions of care as well where there have been a pattern of allegations of systematic abuse.’’

Today, Premier O'Farrell was quick to defend his inquiry, saying it would have all the powers of a royal commission and would consider allegations of a cover-up.

‘‘It is a royal commission by another name. It will get to the bottom of this issue," Mr O'Farrell told ABC Radio.

Mr Rudd’s comments follow calls from several Labor and independent MPs for a more comprehensive investigation.

Senior Labor ministers have condemned reports of child sex abuse in the Catholic church.

Finance Minister Penny Wong described the stories of abuse as ’’heartbreaking’’ but could not speculate on what ’’form’’ an inquiry would take. Senator Wong told Sky News on Monday that any inquiry should be transparent "full, frank and fearless".

Trade Minister Craig Emerson said that he was appalled at the reports and that child abuse should not be tolerated. But he told ABC Radio the government needed to ’’have a discussion about the best way forward’’.

On Monday morning, Labor MP Nick Champion said that it was important to have a broad inquiry that examined any Australian institution that had care of children where allegations have been made - and that dealt with the issue "once and for all".

''We probably do need a royal commission,’’ Mr Champion told Sky TV.

Left faction leader Doug Cameron also backed a royal commission and called on other Labor MPs to support such an inquiry.

''This must be stopped,’’ he told ABC TV, adding that he wanted a commission into the Catholic church only and not on other denominations.

Fellow backbencher Rob Mitchell also backed a royal commission but said he wanted to give the Victorian parliamentary inquiry, currently underway, a chance to wind up first.

Mr Mitchell told ABC TV that caucus needed to have a discussion about a national inquiry when it next met at the end of November.

"These are not isolated issues, these are pretty widespread across the community," he said.

The Victorian MP said that a broader inquiry was needed because the terms of reference for the current investigations were "very tight".

"It’s not allowing victims to have their full say."

Last week in Bali, Ms Gillard said she was concerned about the issue and that she would look at the material when she got home.

''Like every other Australian, I’m very concerned about this issue,’’ Ms Gillard told reporters on Friday.

''I haven’t had the opportunity ... to in detail review the material that is in today’s newspapers.’’

Opposition frontbencher David Johnston said the revelations of child abuse were damaging the reputation of the Catholic church.

"This has been an absolute blot on the landscape in terms of people’s faith and trust in the church," Senator Johnston told ABC TV.

But he noted that a royal commission could be costly. "Remember, royal commissions are very expensive and people have to be cross-examined in giving their evidence," he said.

"The victims are often the last consideration in this, and I am concerned we put them through a court process that aggravates the situation."

Yesterday, Greens leader Christine Milne added her voice to the calls for a royal commission into the Catholic church.

''With unprecedented claims by senior police that evidence is being destroyed or suppressed within the church and that inquiries are being hampered, a national royal commission is needed to address what Cardinal Pell has described as a cancer,’’ Senator Milne said in a statement.

Independent MP Tony Windsor is writing to the Prime Minister to discuss an inquiry.

''The air needs to be cleared,’’ he told ABC Radio on Monday.

Mr Windsor said that since raising the issue over the weekend, he had had an ’’extraordinary’’ number of emails.

He said the royal commission should be Australia-wide because it was a national issue.

Independent senator Nick Xenophon, is also backing a national royal commission and will move a private member’s bill if the government doesn’t act.

"I think it’s important that they do [have one] and if there isn’t a breakthrough on this, if we don’t get to tipping point, I’ll be talking to my federal independent colleagues and crossbench and other colleagues to move a private members’ bill in the parliament early next year," he told ABC TV.

Former prime minister Malcolm Fraser has also called for a royal commission, saying the Catholic church should have nothing to fear from a royal commission if it had nothing to hide.