As its work to approve Boeing’s 737 Max to fly again reaches its final stages, the Federal Aviation Administration has taken public steps to demonstrate that it is using its authority to hold the company accountable and ensure the planes are safe after a pair of deadly crashes.

This week, the agency wrote to Boeing saying its own staff would individually inspect roughly 400 new Max jets before approving them for flight, a responsibility that had previously been shared with Boeing employees.

And when Boeing issued its own estimated timeline earlier this month of when deliveries and flights of the jets would resume, FAA Administrator Stephen Dickson declined to endorse the schedule at a luncheon speech the next day. Instead, he issued a video message to agency staff later that week saying the government “fully controls the approval process.”

“I know there’s a lot of pressure to return this aircraft to service quickly, but I want you to know that I want you to take the time you need and focus solely on safety,” Dickson said. “I’ve got your back.”

The FAA has been under intense scrutiny after two Max jets crashed in a span of five months, killing 346 people and leading the plane to be grounded worldwide. Congressional leaders have questioned how much authority over safety was handed to Boeing and whether FAA managers overruled their own engineers to benefit the company in two cases. They have said the law needs to be changed to redress the balance of power between regulator and manufacturer.

As the FAA has been moving ahead with plans to become more industry-friendly, it has also recently shown that it still has the authority to assert itself when safety is on the line.

Officials have said the agency has held on to all the authority to review design changes to an automated system that was implicated in both crashes, in addition to the plan announced this week to certify individual planes.

The FAA told Boeing in a letter it was taking that second step because so many Maxes had been in storage during the grounding.

“The FAA will retain such authority until the agency is confident that, at a minimum, Boeing has fully functional quality control and verification processes in place,” wrote John Piccola, an FAA official.

Gordon Johndroe, a Boeing spokesman, said the company welcomed the FAA’s letter because of its own commitment to safety.

It remains unclear when the Max will be cleared to fly again, but time is drawing short for Boeing to meet its goal of having the grounding order lifted before the end of the year. Some of the final steps in the process will involve publishing formal notices that the public could be given time to comment on.

When Boeing announced its own expected schedule on Nov. 11, it said there were five milestones that had to be passed. The first had been completed, the company said, but there’s no indication that the second has been.

“We continue to follow the lead of the FAA and global regulators,” Johndroe said. “They will determine when key milestones are achieved and when the fleet and training requirements are certified so the Max can safely return to service.”

Republican leaders on the House Transportation Committee recently sent the FAA questions about its safety oversight work and have said they want to hold public hearings with the FAA’s leaders from 2012 to 2017, when the Max was initially going through the approval process. Committee Chairman Peter A. DeFazio (D-Ore.) has said he supports the idea. A committee aide said Wednesday that a date for a hearing would be announced soon.

Despite the ongoing scrutiny, Boeing has continued to push forward announcing new orders for the troubled jetliner. At the Dubai Air Show earlier this month, the Chicago-based company announced sales of 60 Max jets to Air Astana, which is based in Kazakhstan; SunExpress, a Turkish airline; and an additional third carrier that it declined to name.

Later in the month, the company unveiled the newest version of the Max, the Max 10, which can accommodate up to 230 passengers, more than previous versions of the Max jet. The first flight of the Max 10 is expected next year, Boeing officials said.

“This team’s relentless focus on safety and quality shows the commitment we have to our airline customers and every person who flies on a Boeing airplane,” Mark Jenks, vice president and general manager of the 737 program, said at the plane’s unveiling.

The effects of the Max’s grounding have continued to ripple through the airline industry, with the three U.S. carriers that have the jet in their fleets — American, Southwest and United — announcing this month that they have removed the airliner from their schedules until early March. United, which has 14 of the jets, had previously scheduled the jet to return to service in January. At American, which has 24 of the planes in its fleet, the shift will affect about 140 daily flights.

Even as they announced the change, the airlines continued to express support for the jet’s return to service.

“We remain confident that, once certified by the FAA, the enhancements will support the safe operation of the MAX,” Southwest said in a statement announcing the schedule change. Southwest has the largest number of Boeing 737 Max jets of any U.S. carrier, at 34.

American Airlines chief executive Doug Parker has said he plans to fly on the Max once it is ungrounded. The airline said it will run exhibition flights or flights for employees and guests before the plane resumes regular passenger service.

Dickson has also said he will fly the plane himself and won’t sign off until he would be prepared to put his family on board “without a second thought.”