U.S. aviation safety officials found themselves virtually alone Tuesday, after their counterparts in Europe and around the world ordered hundreds of Boeing aircraft grounded while investigators work to find the cause of an Ethiopian Airlines crash that killed 157 this week.

The Trump administration resisted bipartisan calls to temporarily suspend use of the Boeing 737 Max 8, even as President Trump consulted by phone with the besieged company’s CEO.

With the European Union and others following China’s move to bar flights by some of the American aviation giant’s most important airplanes, former transportation safety officials said the Federal Aviation Administration risked losing its status as the world’s aviation safety leader.

The 737 Max 8, Boeing’s newest plane, has been involved in two crashes in less than six months. The first, in October, killed all 189 passengers and crew aboard a Lion Air flight when the plane plunged into the Java Sea off Indonesia shortly after takeoff.

Former U.S. transportation secretary Ray LaHood, who was a Republican congressman before being appointed by President Barack Obama, said current Secretary Elaine Chao should immediately ground the aircraft.

“Those planes should be pulled down and inspected. The flying public is owed that,” LaHood said Tuesday.

But acting FAA administrator Daniel Elwell said late Tuesday that his agency’s extensive review of “aggregate safety performance from operators and pilots of the Boeing 737 MAX . . . shows no systemic performance issues and provides no basis to order grounding the aircraft.”

Other nations’ civil-aviation authorities had not “provided data to us that would warrant action,” Elwell said.

In a conversation with Trump on Tuesday, Boeing CEO Dennis Muilenburg argued to keep the planes in the sky, according to a senior administration official. The president has not made a final decision on what should be done in response to the Ethiopia and Indonesia crashes, the official said, and is expected to have more meetings Wednesday.

White House officials are working with FAA and Transportation Department officials to determine whether the pilots might have made mistakes or whether there were problems with the plane’s technology or manufacturing, the official said, adding that the administration does not want to make a knee-jerk decision and is concerned that grounding the fleet could have widespread financial effects and cause unnecessary fear.

But a former FAA official, who spoke on the condition of anonymity to talk candidly, said those effects are already being felt, regardless of what the United States does.

“Effectively, it’s grounded anyway,” the former official said. “If all these countries won’t let these planes in, who (cares) what the U.S. allows?”

The United States and Canada have defied the global aviation community in keeping the 737 Max planes in service. Until late Tuesday, FlyDubai was the only other large carrier outside North America using the aircraft. At least 222 planes have been grounded worldwide, according to a Washington Post analysis.

An additional 158 of the aircraft remained eligible for service – largely in the United States and Canada – with slightly more than 100 of them in the fleets of five airlines: American, Air Canada, Southwest, United and WestJet.

The White House has spoken with officials at American and Southwest about the planes, the senior administration official said.

Some observers see parallels between the crash of the Ethiopian Airlines flight and the Oct. 29 Lion Air crash. Both planes were new Boeing Max 8s that went down shortly after takeoff. Both also struggled to gain altitude and appeared to ascend and descend several times before crashing.

But experts say it is too early to determine whether the same problem that stymied the pilots’ ability to control the Lion Air flight – a malfunctioning sensor coupled with an automated response from the aircraft’s software – contributed to the downing of the Ethiopian Airlines plane. Investigators have not determined a final cause of the Lion Air crash.

LaHood said he took the precautionary step to ground planes in 2013, after lithium-ion batteries on Boeing 787 Dreamliners overheated, causing acrid smoke and alarms.

“I consulted with the FAA administrator, and I talked to the CEO of Boeing, and obviously Boeing didn’t like the decision when it was made. But when all the planes were inspected and determined to be safe, everybody was fine,” LaHood said.

LaHood said that he told the White House what he was doing but Obama was not involved.

Chao – whose supporters cited her aviation industry experience as a former member of the board of Northwest Airlines when Trump named her secretary – reiterated Tuesday that her department would take “immediate and appropriate action” if a safety issue were identified.

“The Department and the FAA are working closely with the National Transportation Safety Board, and the Ethiopian accident investigation bureau, to determine the cause of this tragedy as quickly as possible, and to assess any necessary actions going forward,” Chao said.

A Chao spokesman did not respond directly to questions about LaHood or the rush by the international aviation safety community to ground the planes.

Rep. Peter DeFazio, D-Ore., chairman of the House Transportation and Infrastructure Committee, said he wants to know more about the FAA’s decisions regarding pilot retraining on the new Boeing model and suggested that the agency could be conflicted because of its dual role in regulating U.S. aviation and promoting the industry.

Muilenburg’s call to Trump followed tweets by the president complaining that airplanes in general are becoming overly automated. But there had been discussions the night before about setting up the call, a person familiar with it said, and it was not in reaction to the tweets.

“Airplanes are becoming far too complex to fly,” Trump tweeted Tuesday. “Pilots are no longer needed, but rather computer scientists from MIT.”

“Split second decisions are needed, and the complexity creates danger,” the president added. “All of this for great cost yet very little gain. I don’t know about you, but I don’t want Albert Einstein to be my pilot. I want great flying professionals that are allowed to easily and quickly take control of a plane!”

Muilenburg stressed to the president that the planes are safe, the person said.

Since Trump has been in office, the pair have developed a relationship. Muilenburg also called when Trump, as president-elect, took aim at the cost of the new Air Force One that Boeing is building.

Boeing donated $1 million to Trump’s record-size inaugural fund.

The pair later met at Trump’s Mar-a-Lago resort and at Trump Tower to discuss the program.

“Boeing is building a brand new 747 Air Force One for future presidents, but costs are out of control, more than $4 billion,” Trump tweeted in December 2016. “Cancel order!”

In that call, Muilenburg reiterated that “it’s Boeing’s honor to be part of the program,” an official confirmed at the time.

Last year, Trump reached a $3.9 billion deal with Boeing to build Air Force One.

Muilenburg was with Trump when the president called a top Pentagon official to compare the F-35, built by Boeing’s competitor Lockheed Martin, to Boeing’s F/A-18 Super Hornet.

In June, during a meeting of the National Space Council, Trump praised the CEO. “Dennis Muilenburg, friend of mine. A great guy,” Trump said. “The head of Boeing. And, boy, have you done a good job on all fronts – commercial, military.”

And after several CEOs resigned from Trump’s manufacturing council in 2017 over the president’s handling of a white-supremacist rally in Charlottesville, Virginia, Muilenburg kept a low profile and did not speak out against Trump. The president disbanded the council amid growing backlash.

Intense scrutiny of the 737 Max comes as Patrick Shanahan, a former Boeing executive, vies to cement his leadership of the Pentagon. Shanahan, who headed Boeing’s commercial aircraft division during a long career at the aviation company, spent 18 months serving as the Pentagon’s No. 2 before being tapped as acting defense secretary in December when predecessor Jim Mattis unexpectedly resigned.

A senior defense official familiar with Shanahan’s employment at Boeing said that “Shanahan had no responsibility over the 737 Max” while at the company. Another executive had been in charge of the aircraft, which was considered part of a “development program,” the official said.

“Safety is Boeing’s number one priority and we have full confidence in the safety of the 737 MAX,” Boeing said in a statement.

“We understand that regulatory agencies and customers have made decisions that they believe are most appropriate for their home markets. We’ll continue to engage with them to ensure they have the information needed to have confidence in operating their fleets. The United States Federal Aviation Administration is not mandating any further action at this time, and based on the information currently available, we do not have any basis to issue new guidance to operators.”

Chris Nutter, a former Navy pilot and retired airline captain with 21 years at Alaska Airlines, said the variety of responses from safety officials “are all probably prudent under the circumstances. I wouldn’t take alarm with any of these groundings, nor would I take alarm with the continuing operation of the aircraft.”

He said there’s confidence in the FAA and the NTSB’s record of identifying and addressing immediate safety concerns, in the U.S. pilot training program, and in Boeing’s procedures to address problems. The planes are being flown every day in American airways, he said, and pilots would not stay silent if they had concerns.

“When I get in an airplane to fly it, I have a vested interest in the safety of the airplane. We are not going to get on an airplane that we are not fully ready to put our family in and go fly it somewhere,” said Nutter, who teaches aviation at the University of Southern California’s Aviation Safety & Security Program. “Those crews are not going to get on those aircraft if they aren’t safe. All of the politics and money aside, everyone wants to operate and will only operate a safe aircraft.”

But the former FAA official said the agency’s handling of the crisis had become a “debacle” that reflects its responsibility if any gaps in oversight are discovered during the investigation. At issue are sensors, software and other automation technologies that are part of the aircraft, the certification of those features, and the training needed to make sure the aircraft are flown safely.

“You have this huge organization, the FAA, just like you have a huge organization, Boeing, and they have been joined at the hip through all these different variations of the aircraft, including decisions around the design and use of this new system, and everything that follows from this new system, including the manuals and the training,” the former official added. “It’s not just Boeing’s decisions that are being reviewed, it’s the FAA’s.”