Rubio will travel to Samarkand in Uzbekistan, then to Mumbai and Jamnagar between October 17 and 22, according to a State Department announcement reported by CNBC. The itinerary makes no mention of a stop in New Delhi.
The visit comes as the US faces exceptionally high diesel prices that affect truckers, farmers and shippers. The International Energy Agency has warned that constraints on the diesel market will likely keep prices elevated into next year. Earlier this month, President Donald Trump paused sanctions on Russia to allow Moscow's supplies into the global market.
The State Department said Rubio, on his second trip to India this year, will meet senior Indian officials and business leaders "to promote opportunities for commercial investment and economic cooperation."
US Ambassador to India Sergio Gor said the Jamnagar stop was scheduled in light of Reliance's "incredible" investment in a US refinery project, and hinted that Ambani would meet the official. "Given Ambani runs Reliance, I'd imagine he'd be there," Gor told Bloomberg.
Reliance, which is also a key buyer of Venezuelan oil, has "considerable export-oriented refining capacity," Arpit Chaturvedi, South Asia Advisor at strategic advisory firm Teneo, told CNBC, making a strong case for the US to explore refined-product supplies including diesel.
Experts told CNBC the administration is using the trip to focus on business deals rather than policy and politics, with Americans focused on the economy ahead of the midterms. Reliance did not respond to emails from CNBC seeking details on the visit, and the State Department did not respond to queries sent outside working hours.