Narendra Modi addresses during an election rally. File

The nuclear-armed neighbours have fought three wars, and last February came close to a fourth with tit-for-tat airstrikes sparked by an attack on Indian troops in Kashmir.

Modi is under pressure after weeks of protests against a new citizenship law, a slowing economy and the prospect of losing the latest in a string of state elections in New Delhi next month.

"Pakistan has already lost three wars. Our armed forces will not take more than 7-10 days to make Pakistan bite the dust," Modi said in a speech to military personnel.

Pakistan swiftly rejected the "belligerent rhetoric," calling Modi's comments "irresponsible and war-mongering."

A statement from the foreign office said it reflected India's "incurable obsession" with Pakistan."

Wearing a maroon National Cadet Corps baseball cap at the event in the capital, Modi said India's new prowess was thanks to what he called "youthful thinking."

He said that Indian strikes against what New Delhi said were militants in Pakistan-administered Kashmir and inside Pakistan proper in 2016 and last year were evidence of this.

"This is 'youthful thinking'. We carry out surgical strikes and take on terrorists in their homes," Modi said.

Last year, however, an Indian fighter jet was shot down and the pilot captured by Pakistan after a rare aerial engagement.

Agence France-Presse