India and Singapore on Thursday commenced a seven-day joint Navy exercise in the contentious South China Sea where China is asserting itself. Named Singapore-India Maritime Bilateral Exercise (SIMBEX), the joint effort is aimed at increasing interoperability between the two navies. Four warships of the Indian Navy including INS Shivalike, INS Sahyadri, INS Jyoti and INS Kamorta besides long range marmite aircraft P-8l are participating in the SIMBEX and will carry out a diverse range of operational activities at sea, officials said here. The thrust of exercises at sea this year would be on Anti-Submarine Warfare (ASW), integrated operations with surface, air and sub-surface forces, air defence and surface encounter exercises, they said. A number of warships of Singapore Navy including RSN Supreme Formidable, RSN Victory are participating in the exercise along with maritime patrol aircraft Fokker F50 and F-16 aircraft. Held since 1994, it is the 24th edition of the annual exercise between the two countries. The two navies share a long standing relationship with regular professional interactions that include exchange programs, staff talks and training courses. Singapore Chief of Naval Staff, Admiral lai Chung Han had earlier visited and participated in lnternational Fleet Review held in February last year in Visakhapatnam.