A US military plane bringing several tons of much-needed baby formula from Germany landed Sunday at an airport in Indiana as authorities scramble to address a critical shortage.

Scarcity of medical-grade baby formula caused by production problems and supply-chain issues has created grave problems for thousands of parents whose infants rely on it, sending them in frantic searches for the product.

The cargo plane took off from the US air base at Ramstein, Germany, carrying more than 70,000 pounds of powdered formula, the White House said.

President Joe Biden posted about the flight on Twitter from Japan, where he is on a five-day Asia trip.

"Our team is working around the clock to get safe formula to everyone who needs it," he said.

Biden tweeted an update later Sunday, saying more formula was on its way to the United States via a second shipment.

"We have secured a second flight to transport Nestle specialty infant formula to Pennsylvania," the president posted.

"The flight and trucking will take place in the coming days, and I will continue to keep you updated," he said.

The first shipment will cover about 15 percent of the immediate need, presidential economics advisor Brian Deese said on CNN.

He added there are "more flights in train that will be coming in early this week" as part of what the administration has dubbed "Operation Fly Formula."

The formula was flown to Indiana because it is a hub for Nestle, a major domestic producer. It will be quality-tested at a nearby lab before being distributed.

The formula shortage has been developing for months, aggravated not only by supply-chain issues linked to the Covid-19 pandemic but by the closing of the largest US formula-making plant, a Michigan factory owned by Abbott Laboratories, amid concerns that contamination may have led to the deaths of two infants.

"We had a manufacturer that wasn't following the rules, and that was making formula that had the risk of making babies sick," Deese said. "So we have to take action."

Another problem, he said, was that US formula production had become concentrated among just three companies.

"We're going to have to work" on ways to increase competition, he said.

Abbott's CEO, Robert Ford, apologized to consumers in a Washington Post op-ed Sunday, saying: "We're sorry to every family we've let down since our voluntary recall exacerbated our nation's baby formula shortage."

Deese was asked separately about growing concerns that the US economy -- hit by high inflation, supply chain troubles and the war in Ukraine -- may be headed toward a recession.

"Well, there are always risks," he said.

"But there's also no doubt that the United States is in a better position than any other major country around the world to address inflation without giving up all the economic gains that we have had."

The US inflation rate hit a 40-year high of 8.5 percent in March, but slowed slightly in April to 8.3 percent.