In recent years, however, interest in deep sea mining, especially with regard to ferromanganese crusts and polymetallic sulphides, has picked up among several firms now operating in waters within the national zones of Papua New Guinea, Fiji and Tonga. Papua New Guinea was the first country in the world to grant commercial exploration licenses for seafloor massive sulphide deposits when it granted the initial license to Nautilus Minerals in 1997. Japan's new ocean policy emphasizes the need to develop methane hydrate and hydrothermal deposits within Japan's exclusive economic zone and calls for the commercialization of these resources within the next 10 years. Reporting on these developments in his annual report to the Authority in April 2008, Secretary-General Nandan referred also to the upward trend in demand and prices for cobalt, copper, nickel and manganese, the main metals that would be derived from seabed mining, and he noted that technologies being developed for offshore extraction could be adapted for deep sea mining.