India has been one of the latest countries subjected to the Trump administration's frustration due to its growing relations with Russia, including the procurement of the S-400 missiles. After the U.S. warned the country several times to watch its ties with Russia, the Treasury Department finally declared that India could be removed from the U.S.' currency monitoring list of major trading partners on the grounds that India's steps concern Washington.

The U.S. and India are having unsteady relations nowadays as the latter would like to develop its independent foreign policy regarding its ties with certain countries that the U.S. likely considers a threat. While its relations with Iran are closely watched, the latest rapprochement with Russia has frustrated the U.S.

The India deal with Russia to purchase the S-400 long-range surface-to-air missile systems, which was signed during Russian President Vladimir Putin's visit earlier this month, has led the U.S. to take action.

It is not certain that India will be allying with Russia on any other subject, especially critical ones for the region, but the U.S. has already harshened its tone.

In fact is that India and the U.S. have been increasing their cooperation as both are concerned with China's moves. Last year India claimed that Chinese troops made border violations in a contested border area, even killing Indian troops. Therefore India considers the U.S. an ally against China. Similarly, the U.S. believes that India is a crucial partner for securing U.S. hegemony over the Pacific, as both North Korea and China are believed to be determined to break its power.

Moreover, Russia has pledged its support for China and North Korea over the Pacific. In short, the U.S. believes that it is at an important juncture in the Pacific and one of its main allies, India, is leaving it alone. However, the Indian press claims that the Indian government is fed up with external pressure and would like to prioritize its own interests, one of which is the procurement of the missiles.

India was one of the closest allies of the Soviet Union but its relations with Moscow were hampered following the collapse of the Union. Since then, New Delhi has been closer to the U.S. Yet, relations with Russia have improved since 2000. A political initiative, the "Declaration on the India-Russia Strategic Partnership," was aimed at strengthening bilateral ties. Despite this positive stance, India's close relationship with the U.S. has sometimes posed problems. For instance, India has been suffering from the U.S. law, the Countering America's Adversaries through Sanctions Act (CAATSA), which threatens to impose sanctions on certain companies that cooperate with Russia. There are several big Indian companies that could be impinged by that law. Another problematic issue is the defense units of India. According to data provided by the Stockholm International Peace Research Institute (SIPRI) in March, India was Russia's biggest weapons buyer.