President Joe Biden on Wednesday invoked the Defense Production Act to speed production of infant formula and authorized flights to import supply from overseas, as he faces mounting political pressure over a domestic shortage caused by the safety-related closure of the country's largest formula manufacturing plant.

The Defense Production Act order requires suppliers of formula manufacturers to fulfill those orders before other customers. Biden is also authorizing the Defense Department to use commercial aircraft to fly overseas formula supplies that meet federal standards to the U.S., in what the White House is calling “Operation Fly Formula.”

Supplies of baby formula across the country have been severely curtailed in recent weeks after a February recall by Abbott Nutrition exacerbated ongoing supply chain disruptions among formula makers, leaving fewer options on store shelves and increasingly anxious parents struggling to find nutrition for their children.

The announcement comes two days after the Food and Drug Administration said it was streamlining its review process to make it easier for foreign manufacturers to begin shipping more formula into the U.S. Regulators also said Monday that they’d reached a deal to allow Abbott Nutrition to restart its Sturgis, Michigan, plant, the nation's largest formula plant, which has been closed since February due to contamination issues. The company must overhaul its safety protocols and procedures before resuming production.

After getting the FDA’s OK, Abbott said it will take eight to ten weeks before new products begin arriving in stores. The company didn’t set a timeline to restart manufacturing.