Baby formula manufacturer Abbott Nutrition said it has reached an agreement with the Food and Drug Administration (FDA) on a path to restart operations at its Sturgis, Mich., plant.

The facility has been shuttered for more than three months while the FDA investigated whether powdered formula from the plant caused four babies to contract a rare bacterial illness. Two of them died, and a subsequent FDA inspection found unsanitary conditions at the plant.

Abbott said the FDA has not been able to definitively link its formula to the illnesses. The company said it has been making corrective improvements to address the FDA’s concerns.

Once the FDA confirms the initial requirements for startup have been met, Abbott said it could restart the site within two weeks.

The shutdown has significantly worsened an already strained supply chain of infant formula but has hit the parents who rely on specialty formulas the hardest.

Abbott said it would begin production of its specialty formulas first. However, formula from the shuttered plant won’t be on shelves until six to eight weeks after the plant restarts operations.