Islamabad has branded an address by India's foreign minister to the UN in which she accused Pakistan of terrorism in disputed Kashmir as a ‘litany of falsehoods’.

Tensions between the longtime rivals have spiked over a recent attack on an Indian army base in Kashmir that New Delhi has blamed on Pakistan-based militants.

Addressing the UN General Assembly on Monday, Indian Foreign Minister Sushma Swaraj said: ‘Pakistan remains in denial. It persists in the belief that such attacks will enable it to obtain the territory it covets.

‘My firm advice to Pakistan is: abandon this dream. Let me state unequivocally that Jammu and Kashmir is an integral part of India and will always remain so.’

Kashmir has been split between India and Pakistan since the end of British rule in 1947. Both claim the disputed Himalayan territory in its entirety and have fought two wars over it.

The Indian army has blamed the latest attack, in which 18 soldiers and four attackers were killed, on the Pakistan-based militant group Jaish-e-Mohammad.

The group was also implicated in an audacious attack in January on an Indian air force base in Pathankot in the northern state of Punjab, that left seven soldiers dead.

Pakistan responded by calling Swaraj's speech a ‘litany of falsehoods’ that distorted history, and denied its forces had aided the army base attack.

‘These allegations are designed principally to deflect global attention from the brutalities being perpetrated by India's over half a million occupation force against innocent and unarmed Kashmiri children, women and men,’ said a statement by its foreign office released late Monday.

‘Jammu and Kashmir never was and can never be an integral part of India. It is a disputed territory, the final status of which has yet to be determined in accordance with several resolutions of the UN Security Council.’

More than 80 people have been killed in ongoing unrest in Kashmir since July 8 when a young militant leader was shot dead by Indian soldiers, sparking one of the deadliest bouts of violence to hit the region in decades.

Several rebel groups have fought an estimated 500,000 Indian forces deployed in Kashmir, demanding independence for the Muslim-majority region or its merger with Pakistan.

Tens of thousands of people have died in the fighting, most of them civilians.