India agreed a deal with Russia to buy S-400 surface to air missile systems on Friday, the two sides said, as New Delhi disregarded U.S. warnings that such a purchase could trigger sanctions under U.S. law. Although there was no public signing, the deal was sealed during President Vladimir Putin’s ongoing visit to New Delhi for an annual summit with Indian Prime Minister Narendra Modi. The United States has said countries trading with Russia’s defence and intelligence sectors would face automatic sanctions under a sweeping legislation called Countering America’s Adversaries Through Sanctions Act (CAATSA).
