Gerald Ridsdale – arguably Australia's most prolific paedophile priest – has admitted abusing more children who were in his care, but his lawyer has argued his jail term should not be increased.

Ten counts of indecent assault and four of buggery against four boys in the 1970s took to 69 the number of Ridsdale's known victims, the County Court heard on Monday, though it is not known exactly how many lives he damaged over 27 years of offending while a parish priest across western Victoria.

George Pell accompanies Gerald Ridsdale into court in Warrnambool in 1993. Credit:Geoff Ampt

Ridsdale, 85, has been in prison since 1994 and a handful of prosecutions since have increased his overall jail term to 34 years. The earliest he will be eligible for parole is April 2022.

Defence counsel Tim Marsh called on Judge Gerard Mullaly not to increase the non-parole term for a man who has spent 26 years behind bars and whose plea of guilty validated victims who had contacted police.