This article analyses the dynamics of the development of the nuclear rivalry between India and Pakistan and identifies two central factors. First, the India–China border war of 1962 and the latter's accession to the “nuclear club” in 1964, left India with no alternative but to develop its “nuclear option”. Second, the India–Pakistan armed conflicts of 1965 and 1971 prompted the Pakistani ruling circles to develop their own nuclear weapons. This paper examines and evaluates the main stages in the development of the nuclear programmes of India and Pakistan and analyses their impact on the geopolitical situation in the region. It draws attention to the presence of the “China factor” in the bilateral relationship and its influence on the political processes in South Asia. It also highlights the need for the creation of a system of collective security on the Asian continent.