Australia on Wednesday introduced a "no jab, no pay" law which would block parents who refuse to vaccinate their children from accessing some government benefits.
The new legislation introduced to parliament was announced by the government in April.
It was prompted by growing concern about the anti-vaccination movement amid recent outbreaks of preventable diseases - such as measles in Europe and parts of the United States.
There have also been localised outbreaks of whooping cough and measles in Australia.
"Exceptions to the policy will apply only for valid medical reasons, such as when a general practitioner has certified that vaccinating the child would be medically contraindicated," said the wording of the bill.
Australia has vaccination rates of over 90 per cent for children aged one to five, but the government has said that more than 39 000 children aged under seven were not vaccinated because of parental objections.
The number of unvaccinated children has risen by 24 000 over the past decade.
The percentage of children with conscientious objections recorded has risen from 0.23 percent in 1999 to 1.77 percent last year, government data shows.
Former prime minister Tony Abbott said in April that families' decisions not to immunise their children were "not supported by public policy or medical research, nor should such action be supported by taxpayers in the form of child care payments".
The fear that a triple vaccine for measles, mumps and rubella could cause autism has been cited by some people who reject vaccination, even though the theory has been widely discredited by various studies.