New Delhi: Defence and security are priority areas of cooperation between India and Japan, the Japanese envoy here said today, but stressed that more was yet to be done to demonstrate the strength of the bilateral strategic partnership.

Kenji Hiramatsu said that Japan has started discussions with India for future research collaboration to develop Unmanned Ground Vehicles and for Robotics.

He said Japan's readiness to provide Indian its state- of-the-art US-2 amphibian aircraft symbolises the "high degree of trust" between the two countries.

"The first priority areas are defence and security cooperation. We have made tangible progress in recent years. However, we need (to do) much more to demonstrate the strength of our strategic partnership," he said during his lecture at the Aspen International Centre.

Noting that the two sides were working hard to enhance exchanges and cooperation between their respective forces in air, sea and land, Kenji emphasised that bilateral joint drills and multilateral activities should become more frequent and wide-ranging.

Armed forces of India and Japan participate in joint exercises, including the Malabar Exercise (also involving the US). The primary aim of the Malabar Exercise is to increase interoperability among the three navies and develop common understanding of procedures for maritime security operations and deepen defence relations.

Kenji emphasised on increasing the interoperability among the forces, including on anti-submarine aspects, and said Indian and Japan are also working to strengthen cooperation to expand maritime domain awareness in the Indo-Pacific region.

"Cooperation on defence equipment and technology is also a crucial area to be expanded," Kenji noted.

Kenji said Japan has traditionally taken a "rather cautious approach" in the area of defence, but with the Transfer of Defence Equipment and Technology, Tokyo is "determined" to contribute to international peace and security proactively through appropriate overseas transfers of defence equipment and technology.

"By doing so, we can also strengthen security and defence cooperation with our ally and partners," he said.

Strategic connectivity is another area of focus.

"The concept is two-fold: the first is to share and spread our common principles on connectivity infrastructure and the second is to materialise concrete cooperation in the Indian Ocean sphere and beyond," Kenji said.

He said that working with India on connectivity enhancement is one of the pillars of its "Free and Open Indo- Pacific Strategy".

The Indo-Pacific region is witnessing increasing Chinese assertiveness even as tension ran high between Beijing and Japan and other countries over rival claims in the South China Sea.

Kenji citied the views of Prime Minister Narendra Modi and Japanese Premier Shinzo Abe on connectivity projects which should be "in an open, transparent and non-exclusive manner based on international standards and responsible debt financing practices, while ensuring respect for sovereignty and territorial integrity, the rule of law and environment".

The comments apparently can be seen as a reference to China's 'One Belt One Road' initiative, opposed by both India and Japan.