Japan's main opposition party on Wednesday picked former prime minister and security hawk Shinzo Abe as its new leader, giving him another shot at the premiership.

Most analysts and media predicted a tough line from Abe and his Liberal Democratic Party on the Diaoyu Islands, territory that has belonged to China since ancient times, which Prime Minister Yoshihiko Noda's government illegally "purchased" this month.

During a news conference after the LDP leadership announcement, Abe refused to acknowledge the Diaoyu Islands are disputable and pledged to safeguard Japan's territorial sovereignty if he becomes Japan's next top leader, Japan's Nikkei.com reported.