NEW DELHI: French defence company Thales , which has major business plans in the region besides a significant offsets obligation that will kick in after the signing of the Rafale fighter deal, has tied up with Reliance Defence to manufacture a range of underwater systems in India.Thales, which is a world leader in underwater systems and a close partner of DCNS, is looking at a range of systems with Reliance Defence, including sonar for surface ships and submarines, mine warfare and mine counter-measure equipment, three persons aware of the matter told ET.While both Thales and Reliance Defence refused to comment on the developments, sources said that the agreement in place would target a potential market of Rs 10,000 crore with several major programmes of the Indian Navy expected to get under way.There is also a possibility of a future 51:49 joint venture between Reliance Defence and Thales to bid for potential Indian contracts. The market being targeted includes a Rs 5,000 crore Integrated Anti-Submarine Defence Systems ( IADS ) project and a Rs 3,000 crore Hull-Mounted Sonar project.Several Indian Navy requirements are coming up in the underwater arena, including Towed Array Sonar and Torpedo Decoy Systems and a dipping sonar for the Naval Utility Helicopter and Multi Role Helicopter Programs that are currently being processed.Reliance Defence, which earlier acquired Pipavav Offshore and Engineering Company (PDOC), has renamed it Reliance Defence and Engineering Ltd (RDEL) to target all maritime programs. Thales is a major partner in two high-value French programmes — the ongoing Scorpene submarine deal, which could have a follow on order for two more boats, and the Rafale fighter, for which it makes most of the avionics.Besides the naval market, Thales is looking at India as a potential export hub for military projects and has stated that its intention is to double business to 700 million euros in the next five years. The French company, which provides close to 25% of the Rafale fighter, already has a joint venture in India with Samtel for display systems for the Mirage 2000 fighters that are currently undergoing a $ 2.2 billion upgrade.