The risk of exposing a military still being modernized may constrain Prime Minister Narendra Modi as he weighs retaliation for a terrorist attack.

Relations between India and Pakistan are cratering following a deadly militant attack in Indian-administered Kashmir that has sparked tit-for-tat reprisals and raised fears of another military escalation between the nuclear-armed rivals.

The two countries both claim Kashmir in full, but rule it in part. India has long accused Pakistan of helping Islamist separatists who have battled security forces in its part of the territory - accusations Islamabad denies.