After being in the spotlight for personal and business reasons in recent years, following the conviction of Crown employees in China in 2017 for illegally promoting gambling, the Australian billionaire plans to step back from all commitments, said a spokesman, who didn't elaborate on Packer's illness.
As reported by The Straits Times, Crown stock fell as much as 1.7 percent in Sydney trading on Wednesday. The tycoon's private investment company, Consolidated Press Holdings, owns about 47 percent of Crown Resorts.
Wednesday's announcement comes about seven months after Packer returned to Crown's board in the wake of the China crackdown. That ultimately led to Crown's exit from Macau and the closure of most of its Asian offices. Packer has had an on-again, off-again involvement with the company since stepping down as chairman and then as a director in 2015.
"He's a large figure in the business world and there's a lot more scrutiny of what he does than of others," said Evan Lucas, an independent market analyst and consultant based in Melbourne. "He has been under a reasonable amount of pressure. It's a sad story to hear."
Lucas said Crown "will get through it" without Packer because there's enough leadership on the board already.
"Mr. James Packer today resigned from the board of Crown Resorts Ltd for personal reasons," a Consolidated Press spokesman said by e-mail. "Mr. Packer is suffering from mental health issues. At this time he intends to step back from all commitments."
In a rare interview with the Australian newspaper in October last year, Packer revealed he wanted a more "simple life" and acknowledged he had lost friends, put on weight and had led a reclusive life at his polo estate in Argentina.
"It has been a tumultuous four or five years for me," Packer said in the interview.
A separate statement on Wednesday by Crown executive chairman John Alexander didn't elaborate further on Packer's reasons for quitting.
"We have appreciated James' contribution to the board and respect his decision to step down," Alexander said.