The push comes one day after a rights group clashed with Taliban-linked militants in the country's northwest, sparking fresh claims the military was backing proxy forces based in Pakistan that are fighting in Afghanistan.

Sunday's fight between activists from the Pashtun Protection Movement (PTM) and miliants during a rally Sunday left at least two dead and dozens injured on the Afghan border, according to a local official.

PTM has been calling for investigations into disappearances and extrajudicial killings by Pakistan's security establishment, while also echoing accusations that the military allowed extremists a safe haven from which to launch attacks in Afghanistan.

But in a wide-ranging press conference, chief military spokesman Major General Asif Ghafoor slammed accusations that the country was harbouring militants and accused PTM of being manipulated by "enemies of Pakistan".

He went on to defend the conduct of Pakistan's fight against insurgents, noting that thousands had lost their lives in the country's battle against extremism.

"War is a cruel action and not a fair game, more than 70,000 Pakistanis and 16,000 soldiers have been killed and wounded in this war," said Ghafoor during a press conference in the garrison city of Rawalpindi.

Ghafoor was also at pains to emphasise the military's support for elections set in July, as tensions mount following the ousting of former prime minister Nawaz Sharif by the Supreme Court on corruption charges last year.

Since being removed from power Sharif has become increasingly confrontational with the military, repeatedly accusing them of unfairly targeting him and his Pakistan Muslim League-Nawaz party.

Ghafoor said the military stood by Pakistan's political development ahead of what is likely to be only the second democratic transfer of power in the nation's 70-year history.

"There is nobody else happier than the army over the completion of parliament and government's tenure," Ghafoor said.

Pakistan has been under direct military rule for almost half of its existence, with at least 15 heads of states deposed before completing their term, often at the behest of the country's powerful armed forces.