"We expect Boeing to take this bill", it said.
Mr. Trump said the US government had received "new information and physical evidence" both from the crash site and other places, as well as "a couple of other complaints", which led to the decision.
Before Sunday's crash, the 737 Max planes were heavily used, taking more than 9,000 flights in a single week and reaching nearly every continent.
"We are doing everything we can to understand the cause of the accidents in partnership with the investigators, reply safety enhancement and help ensure this does not happen again".
United Airlines said nothing is more important than the safety of its customers and employees and that it will comply.
"It didn't have to be made, but we thought it was the right decision to make", Trump told reporters.
Paul Manafort sentenced to additional 3 1/2 years in prison
He also agreed to co-operate with Special Counsel Robert Mueller's inquiry in a deal for a possible lighter sentence. Manafort apologized for his actions and asked for leniency during a sentencing hearing.
Transport Canada has issued a safety notice restricting commercial use of the Boeing 737 Max 8 and 9 aircraft following the Ethiopian Airlines crash that killed 157 over the weekend.
But there is always a lead time in relation to changes to anything that can affect the safety or operation of aircraft systems that are critical to assuring safe flight. But a brand is at stake as well. The drop has lopped $26.65 billion off Boeing's market value.
The Oslo-based airline has 18 "MAX" passenger jets in its 163-aircraft fleet.
Trump's order also extended to another variant of the plane known as the Max 9.
He said satellite data suggested similarities between the flight profiles of the Ethiopian jet and that of a Lion Air plane of the same type that crashed in Indonesia a year ago.
The pilots said they were able to recover quickly following the aggressive dive - descending as fast as 1,500 feet per minute - by disconnecting the autopilot. Some pilots have reported problems with the jets' software on take-off in other instances.
Shortly after, and possibly because, details of that telephone conversation surfaced, and with Canada bringing down the ban hammer, the FAA was allowed to ground 737 Maxes.
The system prevents the aircraft from pointing upwards at too high an angle, where it could lose its lift. They are voluntary safety reports and do not publicly reveal the names of pilots, the airlines or the location of the incidents. The pilot attempted to stop the software and correct the plane, but ultimately, "the pilot lost that fight with the software".
After the Lion Air crash, Boeing issued a bulletin on what to do regarding erroneous readings from the sensor, which sends out information about what angle a plane is flying at.