The United States, France and Russia, supply weapons and arms to both india and Pakistan according to the Stockholm International Peace Research Institute. Data reveals that Pakistan and India are among the top 10 weapons' importers in the world. Turkey, Serbia, China and Jordan supply weapons solely to Pakistan and not India. Canada, Spain, United Kingdom, Netherlands, Germany, Poland, Israel, Kyrgyzstan and South Korea only provide weapons to India and not Pakistan. One of the things in play is that India sees China as a rival, and a lot of its purchasing is to compete with China. This probably plays into why countries like UK and Germany are only supplying to India, as Pakistan is not the only danger in the region. Pakistan is now the world’s leading purchaser of Chinese weapons.
However, just looking at the arms' race between India and Pakistan, one can conclude that deterrence has been an expensive policy. The massive spending of both countries is a sobering depiction of high-octane missile development programs and lethargic diplomacy.  Indian and Pakistani pledges were to pursue minimum credible deterrence made by government leaders after testing nuclear devices in 1998 has been a sham. The hope was that going public with nuclear capabilities would have stabilizing effects by relieving anxieties and facilitating diplomatic efforts to normalize relations. It did the opposite. Optimists have discounted domestic political and institutional drivers pushing for more bombs and better ways to deliver them. It is a false premise that a sense of normalcy can be midwifed by devices with horrific destructive powers. The number of tangible diplomatic accomplishments since 1998 has been paltry. We have to move beyond doctrines of deterrence.
The overall lack of progress on arms' reduction, as well as apathy and occasionally escalating tensions in the Russia-US dialogue on missile defense and nuclear disarmament, plays havoc with the politics between Pakistan and India as they have no will to jointly influence New Delhi’s and Islamabad’s policies on nuclear arms. Ballistic missiles are developed in a zig-zag fashion. Pakistan and India could choose to use the 1987 Intermediate Range Nuclear Forces Treaty (INF) between the Soviet Union and the United States as a model for their strategic relations and set an equal upper limit for the number of certain types of missiles (if the respective militaries can find it in their egos to do this). We legitimize arms as tools for our survival when they are for our destruction. But when India is importing nearly three times as many weapons as China, what exactly is treaty-less and insecure Pakistan to do?