India has summoned the top Pakistani diplomat in New Delhi, local media reported on Thursday, a day after it announced measures to downgrade ties with Islamabad as relations between the nuclear-armed rivals plummeted following a deadly militant attack in Kashmir.

Relations between India and Pakistan are cratering following a deadly attack in the disputed Himalayan region of Jammu and Kashmir that left more than two dozen tourists dead, raising fears of military escalation between the nuclear-armed rivals.

India's Prime Minister Narendra Modi says the gunmen behind a terrorist attack on tourists in the Kashmir region "will not be spared!"