NEW DELHI/WASHINGTON ¨C U.S. President Donald Trump¡¯s tirade against India over trade and Russian oil purchases threatens to undo two decades of diplomatic progress, analysts and officials say, and could derail other areas of cooperation as domestic political pressures drive both sides to harden their stances.

India¡¯s opposition parties and the general public have urged Prime Minister Narendra Modi to stand up to what they call bullying by Trump, who on Wednesday signed an executive order subjecting Indian imports to an additional 25% in duties on top of an existing 25% tariff, due to its big purchases of Russian oil.

While India has emerged in recent years as a key partner for Washington in its strategic rivalry with China, its large U.S. trade surplus and close relations with Russia ¡ª which Trump is seeking to pressure into agreeing to a peace agreement with Ukraine ¡ª have made it a prime target in the Republican president¡¯s global tariff offensive.

Trump¡¯s taunt that India could buy oil from arch enemy Pakistan has also not gone down well in New Delhi, said two Indian government sources. India has also rejected repeated claims by Trump that he used trade as a lever to end a recent military conflict between India and Pakistan.

In an unusually sharp statement this week, India accused the U.S. of double standards in singling it out for Russian oil imports while continuing to buy Russian uranium hexafluoride, palladium and fertilizer. On Wednesday, it called the tariffs ¡°unfair, unjustified and unreasonable,¡± vowing to ¡°take all actions necessary to protect its national interests.¡±

But New Delhi knows that any further escalation will hurt it in matters beyond trade, said the sources. Unlike China, India does not have leverage like supplies of rare earths to force Trump¡¯s hand to improve the terms of any trade deal, they said.

In recent years, successive U.S. administrations, including Trump¡¯s first, carefully cultivated relations with India with an eye on it as a vital partner in long-term efforts to counter the growing might of China.

But analysts say Trump¡¯s recent moves have plunged the relationship back to possibly its worst phase since the U.S. imposed sanctions on India for nuclear tests in 1998.

¡°India is now in a trap: because of Trump¡¯s pressure, Modi will reduce India¡¯s oil purchases from Russia, but he cannot publicly admit to doing so for fear of looking like he¡¯s surrendering to Trump¡¯s blackmail,¡± said Ashley Tellis at Washington¡¯s Carnegie Endowment for International Peace.

¡°We could be heading into a needless crisis that unravels a quarter century of hard-won gains with India.¡±

Indian state refiners have in recent days stopped buying Russian oil as discounts narrowed and pressure from Trump rose.

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