Pakistan's interior minister says the killing of Pakistani Taliban leader Hakimullah Mehsud has "scuttled" efforts toward peace talks with the insurgent group.
Chaudhry Nisar told a news conference in Islamabad that "every aspect" of Pakistan's cooperation with the United States will be reviewed following the November 1 drone strike that killed Mehsud in North Waziristan, near the Afghan border.
Nisar said an urgent meeting of the Cabinet Committee on National Security (CCNS) had been called to review bilateral cooperation and ties with Washington.
The meeting is expected to take place in the next two to three days, after Prime Minister Nawaz Sharif returns from London.
Nisar said a group of religious leaders was just hours away from setting off to meet the Tehrik-e Taliban Pakistan (TTP) leadership to discuss peace efforts when Mehsud was killed.
Pakistan's Foreign Office said in a statement that it had summoned the U.S. ambassador to Islamabad to protest the drone strike and demand explanations.
The statement said the killing of Mehsud was "counterproductive to Pakistan's efforts to bring peace and stability to Pakistan and the region."
The Afghan Taliban in a statement condemned the killing, which it described as a "terror act by America" and "a big loss."
However, a former senior Taliban official said peace talks should go ahead.
Wakil Ahmed Muttawakil, who served as foreign minister when the Taliban ruled Afghanistan, said that major changes in the leadership of a movement -- such as killing the TTP leader at a time when the Pakistani government is pushing to negotiate peace with the Taliban -- is not good news for the peace talks. "Still," he said, "I think peace talks might take place, and the Pakistani government might like to keep up its efforts, but the pace could slow down."
Taliban sources said Mehsud was buried on November 1 at an undisclosed location in the tribal district.
Meanwhile, the TTP has reportedly nominated a new leader to replace Mehsud.
Taliban sources report that Khan Said, also known as Sajna, was chosen as the new chief of the group. Said, believed to be 36, is the commander of Taliban militants in the South Waziristan tribal district.
Said is believed to have masterminded an attack on a jail in northwest Pakistan that freed nearly 400 prisoners in 2012 and an attack on a naval base in Karachi in 2011.
He was said to be among four candidates considered by the Taliban shura, or council, to replace Mehsud. However, Sajna's nomination was reportedly challenged by some groups within the TTP.
Mullah Fazlullah, the chief of the Taliban faction from the Swat Valley, who is said to be currently based in Afghanistan, was reported to be holding separate meetings to determine his group’s future moves.
Reports say the shura would meet again to try and make a decision.
RFE/RL's Radio Mashaal, RFE/RL's Radio Free Afghanistan contributed to this report, also with reporting by AFP, Dawn.com, and dpa