The presumptive Philippine president-elect has blasted the country's dominant Roman Catholic church as "the most hypocritical institution" and accused some of its bishops of corruption for allegedly asking favors from politicians, including him.

In a late-night news conference that dragged on to early Sunday in southern Davao city, Mayor Rodrigo Duterte questioned the relevance of Catholic bishops, citing his overwhelming victory in the May 9 presidential election based on an unofficial count despite efforts by them to persuade Filipinos not to vote him.

Duterte cursed the bishops, calling them "sons of bitches" and accusing them of benefiting from public money while the poor could not even afford to eat and buy medicine.

Such public condemnation of the influential church by a top leader is rare in Asia's bastion of Catholicism.