NEW YORK (AP) — President Donald Trump on Monday will sign an executive order calling for revamped childhood vaccine recommendations that promote his long-held belief that shots should be spaced out into separate medical visits, according to a White House fact sheet.

The order will recommend administering each vaccine in its own visit and separating the measles, mumps and rubella (MMR) vaccine into three different shots and direct the nation’s health department to improve vaccine research, says the fact sheet, first reported by The Daily Caller. Separate measles, mumps and rubella vaccines for children are not currently available in the U.S.

Public health experts have raised concerns that spacing out shots as Trump suggests can lead to an increased risk that children become infected with a vaccine-preventable disease before returning for another visit. Even as the order calls for revised vaccine recommendations, states, not the federal government, have the authority to require vaccinations for schoolchildren.

Ahead of Monday’s announcement, Trump’s administration had largely pivoted away from talking about vaccine policy in favor of less polarizing topics like healthy eating and efforts to lower drug prices ahead of November’s elections. Polls show most Americans still support school vaccine requirements, though Republicans are less likely than Democrats to see them as important.

Still, Trump has been fixated on connecting autism to vaccines. He has recently ramped up pressure on Health Secretary Robert F. Kennedy Jr. to identify the cause of autism, something Kennedy had pledged to do with new research unveiled last year. Trump publicly prodded the health secretary for an update on autism research in a Cabinet meeting last month.

“How are you doing on the autism research?” Trump asked.

“We will have an answer for you,” Kennedy said.

Scientific consensus and decades of studies have firmly concluded there is no link between childhood vaccines and autism. Childhood vaccines — and how and when to give them in combination — go through rigorous studies, and safety tracking continues for years as the shots are used.

The news comes as school years are starting around the country and the nation contends with a measles outbreak that experts say could result in the U.S. losing its measles elimination status.