(VOVworld) – Japanese Prime Minister Shinzo Abe and US Vice President Joe Biden have pledged stronger cooperation to deal with China’s Air Defense Identification Zone (ADIZ), recently established in the East China Sea.

US Vice President Joe Biden (L) and Japan's Prime Minister Shinzo Abe reach out to shake hands. (Photo: Reuters)

The Kyodo News reported that in a phone call with Abe on Thursday, Biden said he voiced his concern over the air zone in a meeting with Chinese President Xi Jinping last week. Biden called China’s announcement of the ADIZ unacceptable and said it will in no way affect US military operations in the East China Sea. He reiterated the importance of trilateral security cooperation among the US, Japan, and the Republic of Korea (ROK).

Japan and the US have strongly protested China’s unilateral announcement of its ADIZ, which overlaps existing defense zones of Japan and the ROK and the disputed Senkaku/ Diaoyu islands.