Strengthening ties between New Delhi and Tokyo come amid growing concern over China's ascendancy and increasing assertiveness in defense of its national interests.
One look at Indian Prime Minister Narendra Modi's Twitter feed and that of Japanese counterpart Shizno Abe and you'd think they were long lost pals.
The last few days have seen a stream of tweets from Modi – who is currently on his five-day Japan tour – and Abe, professing their mutual admiration.
This is the first major foreign visit by the Indian leader since he took the helm in May.