CH-47 'Chinook' helicopter
A CH-47 'Chinook' helicopter lands during an exercise at the US military base in Grafenwoehr on 10 February 2014Reuters

The Union cabinet on Tuesday cleared a mega deal for purchasing Apache and Chinook helicopters from American aviation giant Boeing, ahead of Prime Minister Narendra Modi's visit to the US.

The Cabinet Committee on Security (CCS) met in New Delhi on Tuesday after a meeting of the cabinet and cleared the proposal worth $2.5 billion, defence ministry sources said.

India would be buying 22 Apache attack helicopters and 15 Chinook heavy-lift choppers, a deal that has been pending since 2013 when Boeing won the tender in a global competition.

In August this year, Boeing gave 13th price extension to India, giving a deadline of September.

The deal was cleared by the CCS after a green signal from finance ministry earlier this week.

The Apache helicopters are meant to replace the Indian Air Force's ageing fleet of Soviet-era Mi-35 attack choppers and will be armed with Hellfire and Stinger missiles.

The Indian Army has also asked for 39 Apache helicopters for its mountain corps, in a separate request.

The deal for Apache is "a hybrid one", with one contract to be signed with Boeing for the helicopter and the other with the US government for its weapons, radars and electronic warfare suites.