A year ago, India quietly stopped selling weapons to Myanmar (Burma.) Five years ago, India had agreed to supply Myanmar (Burma) with weapons and military equipment, and two years ago offered to refurbish Myanmar's aging warplanes (mainly MiG-21s).
India shares a 1,500 kilometer border with Myanmar. That border is in an area where India has had problems with tribal separatists for decades. So supplying heavy weapons (mortars, rifles and machine-guns), a few helicopters and some repairs and upgrades to their MiG-21s, is a way to getting Myanmar to be more cooperative along the border. Some of the tribal rebel groups had established camps just across the border in Myanmar. A more cooperative Myanmar would shut down all those camps, and more aggressively patrol the area, to prevent the Indian tribals from setting up new ones. There has been some such cooperation in the past, and the arms sales were meant to encourage even more.
India and Bangladesh thus made an informal deal with Myanmar to drive rebels from each other's borders. Over the last few years, the three countries have worked out these deals, to rid themselves of rebel groups that had only survived because they could flee across the border and set up camp until their pursuers went away. For decades, Myanmar's neighbors avoided such cooperative relations, as a form of protest against the Burmese military dictatorship. But eventually, the need to deal with various rebel organizations overcame this distaste.
But Myanmar has continued to allow weapons to be sold to tribal rebels in northeastern India. It's believed that the tribal rebels are obtaining 80 percent of their weapons from Myanmar. Diplomacy has failed to stop the weapons coming into India. Myanmar has other sources, primarily China. This is also annoying to the Indians, because they see Myanmar aiding efforts to extend Chinese naval power into the Indian ocean.
Myanmar has been ruled by a military dictatorship for the last 45 years. The generals have run the economy into the ground, and succeeded in suppressing all attempts at establishing a representative government. They have also managed to maintain the support of a fairly large army. How have they managed to pull this off for so long? Simple, the generals have concentrated on maintaining the loyalty of the officers and senior NCOs in the armed forces. This is done by making the military a well paid, by Burmese standards, profession, and select carefully from among those who apply. Meanwhile, Myanmar gets all the weapons it needs from China. Many of the Indian items were free, or cut rate, but it appears that the Chinese have lowered their prices to match that.