Nikola Corp.’s Trevor Milton has approached the company’s board of directors and proposed to voluntarily step aside as executive chairman and from the board.

The board accepted his proposal, and Stephen Girsky, former vice chairman of General Motors Co. and a member of Nikola’s board, has been appointed chairman of the board, effective immediately.

“As we move forward, I am confident Steve is the right leader to guide our vision at the board level,” Millton said. “In addition to being an early believer and supporter of Nikola, Steve has more than 30 years of experience working with OEM leaders, suppliers, dealers, labor leaders and national policy makers, and has served as a director of numerous public companies.”

“We remain committed to delivering on our objectives and creating value for our shareholders,” said Mark Russell, Nikola’s chief executive officer. “Along with the rest of the management team, I will continue to work closely with Steve and the board to advance Nikola’s vision for the future. Our priorities remain unchanged and, in collaboration with our partners, we are laser-focused on executing on our strategic initiatives and laying the groundwork to become a vertically integrated zero-emissions transportation solutions provider.”