Navarro floated Stefan Halper's name for unidentified ambassadorships in Asia, according to the news outlet. Navarro, a harsh critic of China, knew Halper, an academic with a focus on China, from his previous research.
CNBC and NBC News have not independently confirmed reporting in multiple new outlets identifying Halper as an FBI informant. Still, the headlines come at an inopportune time for Navarro, who already is embroiled in workplace controversy after clashing with Treasury Secretary Steven Mnuchin over trade talks with China.
The report will do little to help the trade advisor with Trump, who has raged on Twitter about finding out whether the FBI and Justice Department monitored his campaign. On Monday, the Justice Department asked its internal watchdog to expand an investigation into the methods used to investigate the Trump campaign.
A White House spokeswoman did not immediately respond to a request to comment on the Axos report.