At least 22 suspected Taliban militants were killed by Pakistan army air strikes in northwestern Pakistan, officials said on Wednesday.

The army's media wing Inter Services Public Relations said casualties had been reported in the Datta Khel border town, which sits near the boundary with Afghanistan and is considered one of the last strongholds for Taliban militants.

"Twenty-two terrorists were killed in precise aerial strikes late last night in an area ahead of Datta Khel in North Waziristan," the army said.

The army began anti-militant operations in North Waziristan in June 2014 following the breakdown of peace talks with the Taliban but has in recent months focused more on other parts of the northwestern tribal belt after the Taliban were dispersed from North Waziristan.

The army claims to have killed 2,500 militants but the figures cannot be independently verified. There have been more than 100 soldiers killed in clashes and explosions.

The military operation has displaced nearly a million tribesmen from North Waziristan.