India has halted a key bus service with the Pakistani-controlled part of Kashmir, severing the only land route linking the divided Himalayan region.

Pakistani official Shahid Mehmood said on Wednesday that New Delhi suspended the bus service this week without explanation.

The development comes amid escalated tensions between Pakistan and India in the wake of last week's deadly suicide bombing in Kashmir against Indian paramilitary troops.

New Delhi blamed Islamabad for the attack. Pakistan condemned the attack but cautioned India against linking it to the bombing without an investigation.

An Indian official confirmed the service was halted on Monday. He spoke on condition of anonymity because he was not authorized to talk to reporters.

Kashmir is divided between India and Pakistan, with both claiming the region in its entirety.