The US government has approved the sale of up to nine Boeing Company's P-8A Poseidon maritime patrol planes to Britain in a deal valued at up to $3.2 billion.

The Pentagon's Defense Security Cooperation Agency (DSCA), which oversees foreign arms sales, notified Congress about the potential sale on Thursday.

Lawmakers now have 15 days to block the sale although such action is unlikely given close ties between the US and the UK.

The proposed sale will enhance Britain's capabilities to provide national defense and contribute to Nato and coalition operations, DSCA said in a statement. It said the deal was a top priority for Britain.

Britain announced its intention to buy the submarine-hunting patrol planes in November as part of a five-year plan that will increase spending by 12 billion pounds ($16.96 billion) to 178 billion pounds ($251.60 billion) over the next decade.

At the time, British Prime Minister David Cameron said the planes would help the UK protect its nuclear deterrent and fill a gap left by a much-criticized decision to scrap the Nimrod spy-plane program in 2010.

DSCA said Britain had retained core skills in maritime patrol and reconnaissance following the retirement of the Nimrod aircraft through personnel exchange programs that have left UK forces work on the U.S. Navy P-8A aircraft.

Additional contractors on the deal include ViaSat, Rockwell Collins, Spirit Aerosystems Holdings, Raytheon Company, Northrop Grumman and Harris Corp and General Electric Company.-Reuters