"The allegations are without foundation and utterly false," a statement issued by Pell's office in Rome said after Melbourne's Herald Sun newspaper reported that a police taskforce had been investigating him for over a year over allegations that he abused the boys.
The Herald Sun's revelations prompted global abuse survivors' network SNAP to call on Pope Francis to immediately suspend the 74-year-old from his senior role in the Vatican's bureaucracy.
"That's pretty credible and serious. For the safety of kids, the pontiff should suspend Pell."
Details of the probe emerged a week before Pell is due to give evidence by video link to an Australian inquiry into abuse by priests in the town of Ballarat, near Melbourne.
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The cardinal has been derided for saying he is too ill to make the journey home to testify in person over alleged cover-ups during his time as the head of Australia's Catholic hierarchy.
"The timing of these leaks is clearly designed to do maximum damage to the cardinal and the Catholic Church and undermines the work of the Royal Commission (inquiry)," the statement said.
"It is outrageous that these allegations have been brought to the cardinal's attention through a media leak."
Accusing elements in the Victoria police of trying to smear him, Pell called for a public inquiry into the leak.