Russia and India will sign an agreement on Saturday for Moscow to deliver advanced S-400 surface-to-air missile systems to New Delhi, a Kremlin aide said on Thursday.
Yuri Ushakov, the aide, said the agreement would be signed at an India-Russia summit due to take place in Goa where president Vladimir Putin will hold talks with Indian prime minister Narendra Modi.
India is also hosting a BRICS summit in Goa this weekend involving Brazil, Russia, India, China and South Africa.
Indian defence ministry sources said in December that India's defence acquisition council had cleared the purchase of five S-400 air defence systems from Russia in what one source said was a deal costing around 300 billion rupees ($4.47 billion).
Ushakov did not say how many S-400s were being sold or for how much.
An agreement to build frigates for the Indian Navy would also be signed on Saturday, as well as a deal to set up a joint venture in India to build multi-task Kamov-226 helicopters, he said.
India has long bought military hardware from Russia and the two countries hold join war games every year.
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