"The United Nations is not a neutral body. It is subservient to the United States. I don't expect it to conduct an impartial inquiry," Baitullah Mehsud was quoted as saying in the Pakistani daily Dawn. "We will not work with it."
He dismissed allegations he played a role in the assassination, saying tapes purporting his involvement were manufactured, Dawn reported.
The Taliban commander, who is believed to lead a force of 20,000 militants in Pakistan's south Waziristan provincial area, told a Saturday news conference he stands by a peace deal brokered this week between the government and another militant group.
"The sooner it ends the better it will be," he said of the government dispute.
He vowed, however, to continue fighting U.S.-led forces in Afghanistan, saying the "Jihad in Afghanistan will continue."