Gen. Raheel Sharif says Pakistan's armed forces will react with a "befitting response" to such a move.
In speech Thursday, he also asked the international community to condemn what he called India's "insinuations and fabrications" about Pakistan, which he said has made "unparalleled contributions in the global fight against terrorism."
His remarks came more than a week after New Delhi claimed it destroyed "terrorist launching pads" used by Pakistan-backed militants. Pakistan said it was routine cross-border fire that killed two Pakistani soldiers, the Associated Press reported.
Kashmir, split between Pakistan and India, is claimed by both.