The air forces of India and the United States have taken part in the Cope 18 exercise, an 11-day drill over West Bengal, which ended on Friday. India is also holding exercises with Russian air and ­naval forces. Collin Koh, a research fellow from RSIS in Singapore, said, “These Indian defence and security engagements with foreign powers are likely to bring Indian forces greater ability to work closely with foreign counterparts … complicating China’s strategic and operational military freedom to manoeuvre.”