NEW DELHI: Adding more teeth to the Navys surveillance capabilities, India on Wednesday signed a deal worth over $1 billion with American defence and aerospace major Boeing for procuring four additional Poseidon-8I long-range maritime surveillance and anti-submarine warfare aircraft. The US has emerged as the biggest supplier of military hardware to India and with Wednesday's agreement, the total value of defence deals signed with the US in the last decade comes to around $15 billion.