Sister Patricia Fox, 71, was held by immigration authorities in Manila on Monday for "violating the conditions of her stay by attending protest rallies and engaging in political activities", the BBC reported.
The nun, who has been working in the Philippines for the past 27 years, was released on Tuesday without charge and has denied any wrongdoing. She is also the mother superior of a local Catholic order.
Duterte accused her of "disorderly conduct", warning that foreign critics of his government faced being deported.
"You insult me under the cloak of being a Catholic priest and you are a foreigner. Who are you? It is a violation of sovereignty," he said at an armed forces ceremony in Manila.
"The Philippines laws provide that I can deport you or refuse you entry, if you are an undesirable alien."
Her temporary detention sparked protests from supporters in the largely Catholic country.
Sister Fox is accused of participating in partisan rallies in Mindanao, a restive island in the country's south that is under martial law. However, she denied that her activism was political.
"I have been joining pro-human rights rallies for the farmers -- for their land rights -- (and) to release political prisoners... I would call it part of our duty as a religious (group) that we support the poor," she said.
In his speech, Duterte suggested that Sister Fox should instead scrutinise Australia. "You nun, why don't you criticise your own government, the way you handle the refugees, hungry and dying and you turn them back to the open sea?
"You do not have that right to criticise us. Do not insult my country. We never did that to Australia. We never did that to (a) European country," he said.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
