What Happened India and Russia have finalized a payments mechanism for the $5.2 billion purchase of the Russian-made, state-of-the-art S-400 air defense missile system, according to Vladimir Drozhzhov, an official with Russia's Federal Service of Military-Technical Cooperation. Though specifics regarding the payment mechanism are scant, Moscow and New Delhi have previously floated the possibility of handling their transactions in local currencies, a measure aimed at sidestepping the secondary sanctions Washington has threatened to levy against Russian arms customers — including India — under its Countering America's Adversaries Through Sanctions Act (CAATSA). Why It Matters India's deepening defense partnership with the United States , which views it as a regional ally against China, makes New Delhi subject to greater pressure from Washington over its traditionally cozy ties with Russia.