Russia has started the delivery of S-400 surface-to-air missile systems to India, according to a senior Russian official.
Russia's Director of the Federal Service for Military-Technical Cooperation Dmitry Shugaev told Sputnik news that the deliveries are going as planned.
FSMTC is the Russian government's main defence export control organisation.
"The supplies of the S-400 air defence system to India have started and are proceeding on schedule," he said.
In October 2018, India had signed a USD 5 billion deal with Russia to buy five units of the S-400 air defence missile systems, despite a warning from the Trump administration that going ahead with the contract may invite United States sanctions.
India made the first tranche of payment of around USD 800 million to Russia for the missile systems in 2019.
The S-400 is known as Russia's most advanced long-range surface-to-air missile defence system.
Following US sanctions on Turkey over the procurement of S-400 missile systems, there have been apprehensions that Washington may impose similar punitive measures on India.
Sources in the Indian defence industry said the parts of the air defence system have started reaching India and they would be first deployed at a location close to the Western border from where it can tackle threats from both parts of the Western and Northern borders with Pakistan and China both.
The first squadron deliveries are expected to be complete by the end of this year.
Sources said the equipment is being brought to India through both sea and air routes.
Sources said after the first squadron is deployed, the Air Force would start focusing on the Eastern borders along with providing resources for training of personnel within the country.
Indian Air Force officers and personnel have trained in Russia on the system.
The air defence system would give India an edge in South Asian skies as they would be able to take out enemy aircraft and cruise missiles from 400 km distance.
The S-400 missile defence system is equipped with four different missiles which can engage enemy aircraft, ballistic missiles, and AWACS planes at 400 km, 250 km, the medium-range 120 km and the short-range 40 km.
With inputs from ANI
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