Flight of the Conchords star Rhys Darby and comedian Danny McBride are both believed to be in the frame to take over as the office boss.
"I like Rhys Darby," Liberstein told Fancast. "And Danny McBride is super funny."
HBO recently renewed McBride's comedy Eastbound & Down for a second season. However, Lieberstein insisted that the comic's commitment to the series will not clash with any possible role on The Office.
"We've been having discussions," he explained. "[It] could probably [work]."
A new season of The Office will begin on NBC on September 23.