Satoshi Morimoto said Tokyo’s position had not changed, but confirmed that it would use force to defend the islands known as Senkaku in Japanese and Diaoyu in Chinese.
“Senkaku or not, defence of islands is principally conducted by the coastguard and police,” Morimoto told reporters in Tokyo.
“However, the law stipulates that Self-Defense Forces troops can act” if local authorities are unable to handle the situation.
His comments came a day after Prime Minister Yoshihiko Noda told parliament he would take “stern actions” against any “illegal actions” on Japanese territory.
“If illegal actions are made by neighbouring countries in our territorial soil and waters, including Senkaku, we will take stern actions including using of Self-Defense Force troops, if necessary,” Noda said Thursday.
“(But) it is important that we adopt a solid crisis-management framework and make diplomatic efforts to prevent situations from developing to such an extent,” he added.