The United States has formally notified a proposed sale of sustainment support services and related equipment worth an estimated $482.2 million for India's Apache attack helicopters and M777A2 Ultra-Light Howitzers aimed at enhancing the operational readiness of the Indian armed forces.

The US Defence Security Cooperation Agency (DSCA) -- which administers the Foreign Military Sales (FMS) programme -- has issued the notification in the Federal Register after the Department of State informed Congress last month about the possible sales.

According to the notification, India has requested long-term sustainment support for its M777A2 Ultra-Light Howitzers, including ancillary equipment, spare parts, repair and return services, training, technical assistance, field service representatives, depot-level capability and other logistics support.

The proposed M777 support package is valued at approximately $230 million.

In addition, in a separate notification, the US Department of Defense said India has also sought sustainment support for its AH-64E Apache attack helicopters, including engineering, technical and logistics support services from the US government and contractors, technical publications, personnel training and related programme support.

The Apache support package is estimated to cost $198.2 million.

The principal contractors for the Apache programme will be Boeing Company and Lockheed Martin, while BAE Systems, based in the United Kingdom, will serve as the principal contractor for the M777 howitzer support programme.

India inducted the M777A2 Ultra-Light Howitzers through the US Foreign Military Sales route to strengthen its artillery capabilities, particularly in high-altitude and mountainous terrain.

The US Department of Defense said the proposed sales would support American foreign policy and national security objectives by strengthening the strategic partnership with India.

"The proposed sale will improve India's capability to meet current and future threats, strengthen its homeland defence and deter regional threats," it added.