Boeing Co. will eliminate about 4,000 jobs in its commercial airplanes division by the middle of this year as it looks to control costs, a company spokesman said.

The planemaker will reduce 1,600 positions through voluntary layoffs, while the rest are expected to be done by leaving open positions unfilled, spokesman Doug Alder said.

“While there is no employment reduction target, the more we can control costs as a whole the less impact there will be to employment,” Alder said. The job cuts will include hundreds of executives and managers, but will not done through involuntary layoffs, Alder said.

Reuters had reported last month that the company was considering offering voluntary lay-offs to its professional engineers and technical workers.

In February, Ray Conner, chief executive of Boeing’s airplane business, warned employees that job cuts were necessary to “win in the market, fund our growth and operate as a healthy business”. The Seattle Times had earlier reported that Boeing has taken steps expected to eliminate 4,000 jobs by June.