Australia's Foreign Minister Marise Payne and New Zealand's Foreign Minister Winston Peters urged Japan to remain in the IWC and expressed their governments’ disappointment.
Australia is "extremely disappointed" in Japan's announcement, Payne said in a statement. She urged Japan to return to the pact.
"Australia remains resolutely opposed to all forms of commercial and so-called ‘scientific’ whaling. We will continue to engage with Japan on this important issue in their role as an observer to the commission," she said.
"Whaling is an outdated and unnecessary practice. We continue to hope Japan eventually reconsiders its position and will cease all whaling in order to advance the protection of the ocean’s ecosystems,” Peters said in a statement.
Japan will withdraw from the IWC next year, and will resume commercial hunting in its territorial waters and exclusive economic zone starting in July, Chief Cabinet Secretary Yoshihide Suga said on Wednesday.
Established in 1946, the IWC works to conserve the world's whale population and introduced a moratorium on commercial whaling in 1986 as part of that mission.
Japan will join Iceland and Norway in openly defying the ban on commercial whale hunting.