Boeing CEO Dennis Muilenburg is resigning amid ongoing problems at the company over the troubled Max 737 aircraft.

The Chicago manufacturer said Dec. 23 that Dennis Muilenburg is stepping down immediately. The board’s current chairman David Calhoun will officially take over on Jan. 13. Chief Financial Officer Greg Smith will serve as interim CEO during the brief transition period, while Mr. Calhoun exits his non-Boeing commitments.

The board said a change in leadership was necessary to restore confidence in the company as it works to repair relationships with regulators and stakeholders. The Max was grounded worldwide in March after the second of two crashes of its jet, killing a combined total of 346 people.

New Boeing CEO Calhoun says he strongly believes in the future of Boeing and the 737 Max.

“I am honored to lead this great company and the 150,000 dedicated employees who are working hard to create the future of aviation,” he said.

The leadership change follows Boeing’s announcement last week that it would halt Max production in January.

Then United Airlines said it would pull the Boeing 737 Max from its flight schedule until June. The same day, Spirit AeroSystems, which makes fuselages, said it would end deliveries intended for the Max in January, and Boeing’s new Starliner capsule went off course on a planned trip to the International Space Station.

Board member Lawrence Kellner will become non-executive chairman of the board.

“On behalf of the entire board of directors, I am pleased that Dave has agreed to lead Boeing at this critical juncture,” Kellner said in a prepared statement. “Dave has deep industry experience and a proven track record of strong leadership, and he recognizes the challenges we must confront. The board and I look forward to working with him and the rest of the Boeing team to ensure that today marks a new way forward for our company.”

The shakeup in leadership comes a little after a week that Boeing announced it was suspending production of the troubled aircraft.

On Dec. 16, the company said production of the 737 Max, that has been grounded since March, would stop in January. There are approximately 400 aircraft currently in storage.

Despite Boeing saying there will be no layoffs at the Boeing plant where the 737 max is built, the decision will have ripple effects throughout Boeing’s supply chain, and make further complications for airlines which have lost hundreds of millions of dollars and had to cancel thousands of flights while the aircraft are grounded.

The aircraft were grounded in mid-March following two fatal crashes. On Oct. 29, 2018, A Lion Air flight crashed moments after takeoff in Indonesia, killing all 189 people on board. On March 10, 2019, an Ethiopian Airlines jet crashed shortly after takeoff, killing all 157 people on board.

At this point, there is no way of knowing how long the production halt will last as it is unknown when regulators will clear the plane to fly again.

Editor’s note: Stuart Ibberson contributed to this report.