At least 20 suspected members of the Haqqani network and fighters loyal to local rebel leader Hafiz Gul Bahadur have been killed in air strikes in Pakistan's North Waziristan, officials have said.

Tuesday's attack came in the Doga Madakhel area near the Afghan border after some of the bloodiest incidents in neighbouring Afghanistan were linked to the armed group, including a blast that left 57 people dead at a volleyball match at the weekend.

Pakistan's army said in a text message to journalists on Tuesday that "twenty terrorists were killed in precise aerial strikes in North Waziristan," without giving further details.

The military has been mounting an offensive against rebel strongholds since June.

It was not possible to independently verify the casualties as media are banned from the area.

Two intelligence officials in the northwest told the AFP news agency the had jets targeted hideouts of the Haqqani network and of local rebel leader Hafiz Gul Bahadur.

"The dead included seven fighters of Haqqanis while the rest belonged to Gul Bahadur," one intelligence official told AFP, requesting anonymity.

The second official told AFP that a local Haqqani commander was among the dead, but his identity had not yet been ascertained.

US officials have long urged Islamabad to do more to stop the the Haqqani network using North Waziristan as a base to target Afghan and NATO troops across the border.

Many believe that Pakistan's security services see the group as an "asset" and maintain close links with them, with one senior US official once describing them as a "veritable arm" of the country's ISI intelligence agency.

A day before the airstrikes, a Western diplomat said the Pakistani military and government's stated commitment to pursue all armed rebels was welcome. But the envoy voiced scepticism about whether this had been put into effect.