Taliban commander Hafiz Gul Bahadur said vaccinations would be banned until the CIA stopped its drone campaign that has mainly focused on North Waziristan along the Afghanistan border and considered a safe haven for insurgents, The New York Times reported.
The weekend announcement is a strike against polio vaccination efforts in Pakistan, one of three countries where the disease is still widespread, the World Health Organization says. (The others are Afghanistan and Nigeria.)
The North Waziristan tribal belt is where polio is most prevalent in Pakistan.
A UNICEF spokesman said health workers had intended to give the vaccine to 161,000 children under the age of 5 in a vaccination drive that was to begin Wednesday.
The country's polio campaign caused a furor last year when Dr. Shakil Afridi of Pakistan was linked to a CIA operation to verify Osama bin Laden's whereabouts with a door-to-door vaccination campaign in Abbottabad, where the al-Qaida founder was hiding before he was killed.
Afridi recently was convicted by a tribal court and sentenced to 33 years imprisonment. An appeal filed by his family is to be heard Wednesday.
Bahadur said there was a "strong possibility of spying on mujahedin [Islamic guerillas] for the U.S. during the polio vaccination campaign; one such example is Dr. Shakil Afridi."
Dr. Muhammad Sadiq, surgeon general for North Waziristan, said he received Taliban orders to cancel the vaccination drive.
"Under these circumstances we cannot continue," he told the Times in a telephone interview.