The Vatican on Monday urged Catholics to get vaccinated against coronavirus and said it was "morally acceptable" to take vaccines that use cell lines from aborted foetuses.
Cells derived from foetuses aborted decades ago have been used by some researchers racing to find a vaccine against coronavirus.
The Vatican acknowledged that the issue was a cause of concern for some Catholics but said in a note that "it is morally acceptable to receive Covid-19 vaccines that have used cell lines from aborted foetuses in their research and production process".
The use of such vaccines "does not constitute formal cooperation with the abortion from which the cells used in production of the vaccines derive," it said.
The Vatican added that while vaccination "must be voluntary... in the absence of other means to stop or even prevent the epidemic, the common good may recommend vaccination, especially to protect the weakest and most exposed".
Those who refuse to use vaccines "must do their utmost to avoid" spreading infection, it added.
The note also highlighted the "moral imperative" of the pharmaceutical industry, governments and international organisations to ensure that vaccines "are also accessible to the poorest countries".