NEW DELHI, Aug 6 (Reuters) - Indian Prime Minister Narendra Modi will visit China for the first time in over seven years, a government source said on Wednesday, in a further sign of a diplomatic thaw with Beijing as tensions with the United States rise.

Modi will go to China for a summit of the multilateral Shanghai Cooperation Organisation that begins on Aug. 31, the government source, with direct knowledge of the matter, told Reuters. India's foreign ministry did not immediately respond to a request for comment.

His trip will come at a time when India's relationship with the U.S. faces its most serious crisis in years after President Donald Trump imposed the highest tariffs among Asian peers on goods imported from India, and has threatened an unspecified further penalty for New Delhi's purchases of Russian oil.