By Jarrett Renshaw (Reuters) -U.S. President Joe Biden will meet with major infant formula manufacturers on Wednesday as his administration presses ahead with efforts to boost imported supplies to help ease a nationwide shortage. Multiple global suppliers are seeking U.S. approval to ship critical baby formula as Biden’s administration accelerates what it has dubbed “Operation Fly Formula” to help fill store shelves and calm frustrated parents. The latest effort includes announcement on Wednesday that United Airlines has agreed to transport U.K.-made Kendamil formula free of charge from Heathr…