U.S. President Donald Trump's India tariffs have shown Moscow's allies that he will follow through with his threat to impose secondary tariffs on countries that purchase Russian oil, though doubts remain about the practicalities of implementing them,

U.S. President Donald Trump's demand on India to halt Russian oil imports could threaten billions in Russian revenues, prompt Moscow to retaliate by stopping a major U.S.-led oil pipeline and potentially lead to a new global supply crisis.