U.S. Ambassador to the U.N. Nikki Haley announced her resignation Tuesday after a watchdog group demanded that the State Department investigate private flights she accepted from South Carolina businessmen while serving in her current role.
[READ: Nikki Haley's letter of resignation]
Citizens for Responsibility and Ethics in Washington filed a request Monday with the State Department's inspector general asking that Haley be investigated over seven free flights on luxury aircraft she and her husband were gifted by three prominent executives in her home state of South Carolina.
The nonprofit organization, known as CREW, estimated that the air travel between New York, Washington, and three cities in South Carolina was worth "tens of thousands of dollars" to the ambassador.
In a press release, CREW said Haley's 2017 public financial disclosure report stated the flights were not prohibited by federal ethics regulations because of her personal relationship with the men.
"The report, however, does not provide enough information to demonstrate that this exception was applicable to the flights," the group wrote in a statement. "Whether the exception applies depends partly on whether the three businessmen were the only sources of the gifts; if business entities were sources of the gifts, the exception was inapplicable."
CREW added that Haley should have been cognizant that using the planes would have created the appearance of impropriety given the political problems experienced by other Trump administration officials.
Haley confirmed Tuesday she would be departing the top diplomatic post at the end of the year during a White House press event with President Trump in the Oval Office.