The residents of Pakistan's restive tribal belt will not be able to travel to other parts of the country without getting vaccinated against polio.
The move came days after Pakistan said it would set up mandatory immunisation points at airports to help stop its polio outbreak spreading abroad, in response to new guidelines by the World Health Organization (WHO).
"(The) Prime Minister decided to involve (the)... Army to ensure security on all FATA (Federally Administered Tribal Area) border points to regulate ingress of people from FATA into settled areas only after polio vaccine has been administered," a statement from prime minister Nawaz Sharif's office said.
The Taliban and other militants violently oppose polio vaccination campaigns, seeing them as a cover for foreign spying and regularly attacking immunisation teams.
Some 56 people have been killed in such incidents since December 2012.
In response to the attacks, officials in April said they would begin administering polio vaccines to children at security checkpoints in the country's lawless tribal belt.
Militants' opposition to immunisation has increased since Pakistani doctor Shakil Afridi helped the CIA track down terror chief Osama bin Laden in 2011 through a fake vaccine project.
Widespread public fears that the vaccine leads to infertility have also contributed to a re-emergence of the disease in Pakistan.
The country recorded 91 cases of polio last year, according to the WHO, up from 58 in 2012. It has also recorded 59 of the world's 74 cases this year.
The WHO had called on Pakistan, Cameroon and Syria -- seen as posing the greatest risk of exporting wild poliovirus -- to ensure all residents and long-term visitors receive a polio vaccine between four weeks and a year before travelling abroad.
India, which recently celebrated the eradication of the disease, announced in December it would require Pakistanis to obtain vaccination certificates six weeks before cross-border travel.