Cardinal George Pell, Head of the Catholic church in Australia, gives a press conference at St Mary’s Chatedral in Sydney December 20, 2009.  REUTERS/Daniel Munoz

The head of Australia’s powerful Catholic Church acknowledged the “shame” of child sex abuse among the clergy and welcomed a sweeping inquiry, but also warned that the extent of the problem within his church had been exaggerated.

On Monday, Prime Minister Julia Gillard ordered a rare Royal Commission, the highest form of investigation in Australia, into how churches, government bodies and other organisations have dealt with possibly thousands of child sex abuse claims.

George Pell, Australia’s only cardinal, said the Church would cooperate fully with the new inquiry, which can compel witnesses to give evidence and produce documents, and that he did not believe the Catholic church was the main perpetrator.

“We are not interested in denying the extent of misdoing in the Catholic church. We object to it being exaggerated, we object to it being described as ‘the only cab on the rank’,” said Pell, who is also Archbishop of Sydney, on Tuesday.