The United States has just approved a deal valued at more than $3 billion with India on Tuesday, US President Donald Trump announced, at the start of his two-day official visit to the South Asian country.

Trump has confirmed that a long-expected military contract with India to buy US-made combat helicopters will be signed during his trip to the country. Trump also listed other key areas of cooperation between the two nations.

Just a few weeks ago, officials from the US State Department approved the sale of a Raytheon Air Defense Weapon System, which includes missiles and radar, to India as part of a $1.87 billion deal.

"The US makes the best weapons in the world and we are dealing now with India," Trump told some 100,000 cheering crowd at India's western city of Ahmedabad as the president shared the stage with Indian Prime Minister Narendra Modi.

The American commander in chief said he was very happy to sell India the "absolute" best helicopters available in the market today. Expressing his optimism that New Delhi and Washington will become a "premier defense partners," Trump boasted that his country makes the "most feared military hardware on the planet."

Last week, India approved the acquisition of 24 Lockheed MH 60R Seahawk helicopters with a price package of $2.6 billion. Shares of Lockheed was down 2 percent late Monday amid a broad market selloff, based on the MarketSmith chart. Among other defense stocks, Raytheon also dropped 2.7 percent, and Boeing shed 3.7 percent, General Dynamics lost 1.7 percent, and Northrop Grumman eased 1.4 percent.

The US and India, Trump said, are in the initial stages of talks for an "incredible trade deal to cut barriers of investment between the two countries." "I am positive that, working together, the prime minister and I can sign a fantastic deal that is great for both of our nations."

Trump said that he wants to see stronger cooperation in space exploration with India, which has already tapped the support of another space superpower - Russia - as the country sent four astronauts for training for their first manned mission, set to take off in 2022.

The agreement comes as Lockheed and Boeing bid to seal a fiercely-contested warplane deal valued at over $15 billion with India, in what could be an even challenging windfall for defense stocks. Overseas defense stocks Dassault, Saab and Russia's United Aircraft Corp., which manufactures the MiG combat aircraft, is also competing.