India is poised to sign a $7 billion weapons deal with Russia before Christmas, securing advanced missile technology, submarines and frigates, according to a report Monday from the left-leaning Moscow daily newspaper Kommersant. It’s expected that the deal could be signed when Indian Prime Minister Narendra Modi visits Russian Prime Minister Vladimir Putin, scheduled for Dec. 24-25.

New Delhi has already cleared the way for the country to spend $2.5 billion on five S-400 systems, but Moscow is said to be reluctant to proceed until India finalizes a $10 billion deal for the stealth T-50 fighter jet. If the deal is completed, it will make India the second foreign buyer of the advanced missile system after China. Iran is also expected to receive one S-400 once missile sanctions against it expire or are revoked.

India is one of Moscow’s biggest customers along with China, spending billions each year on Russian weapons. A recent report by the Stockholm International Peace Research Institute showed that Russian arms sales had increased by nearly 50 percent from 2013 to 2014, according to the latest reliable data available. Developing economies with large military ambitions often look to Russian for technologically advanced and cheap weapons, whereas purchases from the West are more expensive and harder to obtain.

On top of the possible S-400 deal, India also wants to discuss a possible purchase of two Varshavyanka-class diesel-electric submarines, 48 Mi-17V-5 military transport helicopters, 150 BMP-2/2K armored fighting vehicles and three Project 11356 frigates.

“We are also waiting for the decision on leasing the second nuclear Project 971 submarine,” an unidentified source in the military-technical cooperation told Kommersant.

The S-400 is capable of intercepting and destroying airborne targets at distances up to 400 kilometers (250 miles), while engaging six targets at once. A domestic version that India is reported to be building will not be as good as the Russian system, which is said to be more advanced than the U.S.-built Patriot missile system, according to Russian reports.