Chief of Defence Staff Gen Bipin Rawat said on Friday that border confrontations, transgressions and unprovoked tactical military actions spiralling into a larger conflict cannot be discounted.
In an address at a virtual seminar, Gen Rawat said the situation along the Line of Actual Control (LAC) in eastern Ladakh remains tense.
He also stated that China's People's Liberation Army (PLA) is facing "unanticipated consequences" for its misadventure in eastern Ladakh because of the "firm and strong" responses by the Indian armed forces.
"Our posturing is unambiguous. We will not accept any shifting of the Line of Actual Control," he asserted.
The Chief of Defence Staff also touched on the issue of cross border terrorism from Pakistan and the way it has been dealt with by the Indian armed forces.
Referring to security challenges, Gen Rawat said the "constant friction" with the two nuclear-armed neighbours (Pakistan and China) poses a danger of regional strategic instability with the potential for escalation.
He also suggested that the two countries with whom India had fought wars are increasingly acting in cohesion.
The Chief of Defence Staff said the "unabated proxy war" unleashed by Pakistan in Jammu and Kashmir accompanied by "vicious" anti-India rhetoric have taken the ties between the two countries to a new low.
"The surgical strikes after the Uri attack and Balakot airstrikes have delivered a strong message that Pakistan no longer enjoys the impunity of pushing terrorists across the LoC under the nuclear bogey," Gen Rawat said at the seminar organised by the National Defence College.
He said the new Indian template to deal with terrorism has injected ambiguity and uncertainty in Pakistan, adding India will confront terrorism with a firm hand.
The Chief of Defence Staff said despite internal problems, failing economy, international isolation and vitiated civil-military relations, Pakistan will continue to "profess" that Kashmir is their "unfinished agenda".
"And their Army will continue to raise the bogey of an existential threat from India to justify their disproportionately large strength and need for funds to maintain its warfighting capabilities," said Gen Rawat.
(With inputs from PTI)