A suspected US drone attack along the Pakistani-Afghan border killed an Islamist militant commander from the Taliban-allied Haqqani Network, said a Pakistani official and two members of the Haqqani group yesterday.

The Pakistani official said it was not immediately clear whether the missile struck on the Afghan or Pakistani side of the border. The members of the network and an eyewitness reached by Reuters said the incident took place inside Pakistan.

There have been multiple suspected U.S. drone strikes in the mountainous border region separating Pakistan's Kurram Agency from Afghanistan since U.S. President Donald Trump took office in January.

Trump has taken a hardline stance on Pakistan, which he says provides safe haven to terrorists including the Afghan Taliban and the Haqqani Network carrying out attacks in Afghanistan.

Yesterday's suspected drone attack targeted the vehicle of a militant commander named Jamiuddin, said the Pakistani official, who is based in the area, speaking on condition of anonymity, added that it also killed an associate of the commander.

A senior member of the Haqqani network told Reuters: "Maulvi Jamiuddin was our trusted man. He was part of our organisation and used to facilitate our fighters during their movement inside Afghanistan."

He added that Jamiuddin was travelling in his car in Pakistan's Kurram region and that none of his associates were killed in the attack.

"Jamiuddin stopped the car ... for conversation on his cellular phone when the drone fired two missiles and killed him on the spot," another Haqqani member said.

Rehmanullah, a resident of the area who uses only one name, said he saw the strike near the Mata Sanghar area of Kurram agency, across from the Afghan province of Paktia.

"I saw two missiles hit the vehicle and the people inside were killed," he told Reuters by telephone.

An increase in drone strikes that hit inside Pakistani territory is one of the steps U.S. officials have said could be taken if Islamabad does not end safe havens for militants.