In October 2018, India inked the historic agreement worth US$5.43 billion with Russia to procure four S-400 Triumf surface-to-air missile defence system, one of the most powerful missile defence systems in the world ignoring America's CAATSA act. The U.S. threatened India with sanctions over India's decision to buy the S-400 missile defense system from Russia. The United States also threatened India with sanctions over India's decision to buy oil from Iran. According to the President of the U.S.-India Strategic Partnership Forum (USISPF), Mukesh Aghi: "sanctions would have a disastrous effect on U.S.-India relations for decades to come. In India’s eyes, the United States would once again be regarded as untrustworthy."