Tonga's new leader, Lord Fakafānua, supports US partnership.
Concerns raised about environmental impacts of deep-sea mining.
Deal aims to explore deep-sea minerals in the Pacific.
Strategic angle: Pacific island’s new leader discusses ‘exciting’ US partnership as critics fear impacts of seabed exploration.
Tonga's new leader, Lord Fakafānua, supports US partnership.
Concerns raised about environmental impacts of deep-sea mining.
Deal aims to explore deep-sea minerals in the Pacific.