India and the United States will soon sign their biggest arms deal, with the government giving the nod for the purchase of six C-130J Super Hercules transport aircraft at an estimated cost of Rs 4,000 crore.

"The Cabinet Committee on Security has cleared the deal", defence minister A K Antony said.

The clearance for the deal comes a month ahead of the first ever visit to India by new US defence secretary Robert Gates on February 25.

The sale, Antony said, would be under a government-to-government FMS scheme.

This will be the third major arms deal with the US. Recently, India purchased the 45,000 tonne displacement USS Trenton, a shiplanding dock, now rechristened INS Jalashva for about $500 million.

Three years ago India and the US had concluded a deal for the purchase of seven weapon-locating radar ANTPQ-37.

The C-130J, manufactured by US aviation giant Lockheed Martin, is being bought in special forces configuration and would come with equipment like missile warning system, radar warning receiver and counter measure dispensation.

India's version of the Super Hercules is believed to be far more advance than those supplied by the US to Pakistan.

This is the first time since the 1962 war with China that the Indian Air Force will sport an American aircraft in its armoury.

The American aircraft has the capability to land on makeshift strips and even in the complete dark and radio silence conditions, which India lacked during the Kandhar hijacking.