Trump signed the executive order at an Oval Office event where he discussed previous comments linking childhood shots and autism. Scientists have said the connection is unfounded, according to the Wall Street Journal.

The order urges parents to space vaccines across more pediatrician visits and encourages states to mandate fewer vaccines for school attendance. A third provision directs the administration to find alternatives to aluminum, which the Journal described as a common vaccine ingredient.

The Wall Street Journal reported that it is unusual, if not unprecedented, for detailed vaccine policy to emerge from the White House. It was not clear how the vaccine recommendations would be implemented.