Will the US sanction India over its Russian S400 missile purchase?

India and Russia recently reiterated their commitment to finalise the S400 missile defence deal that has seen the US threaten New Delhi with sanctions.

The tensions between New Delhi and Washington are a far cry from the speech the Indian Prime Minister Narendra Modi made in the presence of the then-Vice President Joe Biden in June 2016.

"The constraints of the past are behind us, and foundations of the future are firmly in place," said Modi to a joint session of Congress in the US.

While India has become more important for the US as it seeks to corral countries against China, New Delhi isn't ready to sacrifice a relationship with Russia that goes back decades to the early days of the Cold War.

India signed a $5.5 billion deal for five regiments of the S-400 system in 2018, however, the defence system is yet to be delivered.

Now the Biden administration is under pressure from Senators from the Democratic party to sanction India.

The Chair of the US Senate Foreign Relations Committee, Senator Bob Menendez, recently called India's planned purchase of the Russian S-400 missile defence system a "matter of concern."

"If India chooses to go forward with its purchase of the S-400, that act will clearly constitute a significant, and therefore sanctionable, transaction with the Russian defence sector under Section 231 of CAATSA," added Menendez referring to the 'Countering America's Adversaries Through Sanctions Act.

The Russian S400 is an advanced anti-aircraft missile system boasting a range of 400 kilometres which was introduced in 2007. Since then, it has become central to the country's anti-aircraft defence system.

It was only in March that leaders of Australia, India, Japan and the US met for the Quadrilateral Security Dialogue. The group, also known as 'the Quad', is increasingly a forum for resisting China.

Sanctions by the Biden administration on India could see disunity emerge between earnest allies as they confront China while also pushing India closer to Russia.

The delicate balancing act will also have to contend with another US ally that has bought the S400 missile system, Turkey.

The Trump administration, in its dying days, imposed sanctions on Turkey for purchasing the S400 missiles in 2019. The issue is still a source of deep contention between Ankara and Washington.

But if the Biden administration gives India a waiver, why not Ankara, will be the thinking for politicians in Turkey.

Japan and Australia have been keen to confront China and seek the US' help in the process, India, however, has had an extended policy of non-alignment. In the Quad membership, India has been reluctant to jump on the anti-Beijing bandwagon despite its problems with China.

Sanctions by Washington could well spook New Delhi.

India's weapons procurement from the US is also on the increase. In 2020, India purchased more than $3.4 billion in weapons from the US as it seeks to modernise its military, up from $6.2 million in 2019.

Given India's experience of colonialism and an economy in the ascendancy, India is unlikely to take kindly to threats of sanctions or lectures on democracy from Washington.

Under the US sanctions regime, India may well receive a waiver as broader American interests are at stake, however, Turkey may not look kindly at such exceptions.