The Twitter exchange was a prelude to a big bear hug on Saturday, as Mr Modi, with a high-powered Indian business delegation in tow, began a five-day visit to Japan aimed at taking take his blossoming relationship with Mr Abe to the next level.
Saturday's clinch outside the Kyoto State Guest House was remarkable for two reasons. Mr Abe, who normally receives dignitaries in Tokyo, had made a special trip to the ancient Japanese capital in what Kyodo news agency described as "an extraordinary gesture of welcome."
And by throwing his arms around his guest, the normally diffident Japanese premier marked a sharp contrast from the firm handshake with which he greeted U.S. president Barack Obama in April.
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The Japanese and Indian leaders have much in common. As Ruchir Sharma, head of emerging markets at Morgan Stanley Investment Management, wrote, both are "conservative nationalists and pro-business reformers, who promised to restore national pride by reviving troubled economies."
But Mr Modi's decision to make Japan his first foreign port of call beyond India's immediate South Asian neighbourhood since his May election is based on far more than his personal chemistry with the Japanese premier. It is informed by hard-nosed calculations of how India and Japan can work together on undertakings of mutual interest and concern – reviving their respective economies, and grappling with Chinese expansionism.