WASHINGTON (AP) — A massive recall is getting most of the blame for the U.S. baby formula shortage, but experts say the products have long been vulnerable to this type of crisis due to decades-old policies that have allowed a handful of companies to corner the market.

Those government rules — aimed at assuring safe, affordable formula — are getting renewed scrutiny as President Joe Biden’s administration rushes to import formula from Europe.

“There’s perfectly good and safe baby formula available around the world. We just don’t have access to it,” said Bindiya Vakil, CEO of Resilinc, a supply chain analytics firm. ”We’ve created this problem by not setting up an infrastructure for imports.”

Abbott Nutrition said Tuesday it expects to restart its shuttered Michigan plant June 4 and begin shipping new formula to stores about three weeks later. The factory is the largest of its kind in the U.S. and has been closed since February, hobbling supplies of popular formulas and specialty formulas for children with rare medical conditions.