(CNN) - Some high-profile Democrats are heading to Park City, Utah this summer to attend a policy retreat held by former Republican presidential nominee Mitt Romney.
According to the guest list, obtained by CNN from a source close to Romney, former senior adviser to President Obama's re-election campaign, David Axelrod, and outgoing Los Angeles Mayor Antonio Villaraigosa are among those expected to attend.
"As our June gathering approaches, I wanted to give you an update on some of the people who will be addressing us," Romney wrote in the email. "I have drawn speakers from government and business to identify key opportunities ahead. And I have made sure to invite presenters from both sides of the aisle."
As CNN previously reported, Romney's former running mate, Rep. Paul Ryan, and Republican Gov. Chris Christie of New Jersey are also scheduled to appear at the event.
Others include Erskine Bowles and Alan Simpson, co-chairmen of the National Commission on Fiscal Responsibility and Reform, American Enterprise Institute President Arthur Brooks, Hewlett-Packard CEO Meg Whitman, Founder of Sun Microsystems Scott McNealy, and Harvard Business School Clayton M. Christensen.
In a previous email to invitees last month, Romney said Solamere Group, the private equity firm founded by his son Tagg and where Romney now serves as a chairman, will help sponsor the gathering.
Romney hosted a major retreat for approximately 700 donors last summer in Park City, featuring speeches by many of his top campaign staff and prospective vice presidential picks.
At a major gathering last month for conservatives-where Romney made his first public speech following his election loss in November-the former Massachusetts governor expressed intent on staying engaged in public policy.
"I am sorry that I will not be your president," he said. "But I will be your co-worker, and I will work shoulder-to-shoulder alongside you."
- CNN's Ashley Killough and Kevin Bohn contributed to this report.