The US Congress on Thursday formally notified the possible sale of 31 MQ-9B high altitude long endurance armed Unmanned Aerial Vehicles (UAV) to India.

The Defence Security Cooperation Agency (DSCA) said in a statement: "The State Department has made a determination approving a possible Foreign Military Sale to the Government of India of MQ-9B Remotely Piloted Aircraft and related equipment for an estimated cost of $3.99 billion."

"This proposed sale will support the foreign policy and national security objectives of the United States by helping to strengthen the U.S.-Indian strategic relationship and to improve the security of a major defense partner which continues to be an important force for political stability, peace, and economic progress in the Indo-Pacific and South Asia region," the statement said.

DSCA said the proposed sale will improve India’s capability to meet current and future threats by enabling unmanned surveillance and reconnaissance patrols in sea lanes of operation.

Meanwhile, commenting on the deal,  Matthew Miller, a spokesperson for the US State Department, told media: " This was the initial step today, notifying Congress. The exact timeline of the delivery is something that we will explore with the Government of India over the coming months."

"I will say with respect to the deal itself, the $3.99 – almost 4 – billion sale of 31 MQ-9B SkyGuardian aircraft will provide India with an enhanced maritime security and maritime domain awareness capability," he said.

Miller said: "It offers India outright ownership and a 16-fold increase in the number of aircraft, as compared to their current lease of two MQ-9A aircraft."