Australia has thrown its support behind Japan's bid to build a missile defence system in response to perceived threats from North Korea. The backing came during talks in Tokyo between Australian Defence Minister Robert Hill and his Japanese counterpart, Shigeru Ishiba. They signed an agreement to increase contact between military officials and allow for joint exercises. It will also boost co-operation in counter-terrorism and tackling weapons of mass destruction. Japan wants a defence shield in order to protect itself from the threat of a missile attack by North Korea which could reach the Japanese islands in less than 10 minutes. Australian and Japanese forces last month took part in exercises designed to test their ability to intercept ships suspected to be carrying weapons of mass destruction - drills widely seen as targeted at North Korea.