Boeing's P-8I Poseidon is close to winning India's competition for eight maritime patrol aircraft, providing further evidence of the country's growing defence ties with the USA.

New Delhi has been in price negotiations with Boeing for the $2 billion, eight-aircraft requirement since December, while officials from EADS Casa - which is leading a rival bid based on the Airbus A319 - have not heard from Indian officials.

With the bids due to expire on 31 March, sources close to the defence ministry expect a deal with Boeing to be sealed soon. "If necessary, the ministry could ask the candidates to extend the deadline by a few months. - but they want to wrap this up as soon as possible," says one source.

This follows India's pending $1 billion order for six Lockheed Martin C-130J tactical transports, plus options on six more - New Delhi's first order for US military aircraft for several decades. A contract award is expected later this year.

But observers caution that nothing is confirmed in India until the deal has been officially signed. Last year, for example, Eurocopter was close to clinching a $500 million contract for 197 light utility helicopters until the tender was cancelled at the last minute because of unconfirmed allegations of irregularities in the bid.

EADS officials have argued that their MPA bid is almost 20% cheaper than Boeing's, and that the USA could restrict the transfer of technology to foreign buyers of the P-8. But Boeing officials have denied those charges. "We are the only ones negotiating with the Indians - and that says it all," says one.

The P-8A will be delivered to the US Navy from 2009, and India's aircraft are likely to be inducted from around 2013 to replace ageing Ilyushin Il-38s.

The mission uses developments of sensors already operational in USN Lockheed P-3Cs, but India's P-8I variant would allow the integration of indigenous systems, such as communications, datalink and identification friend-or-foe equipment.

A follow-on order is expected from India early next decade.