United Airlines chief executive Jeff Smisek has stepped down from the role amid an investigation into corruption at the carrier.

Federal authorities are investigating whether Smisek sanctioned an unprofitable flight in order to benefit the head of the Port Authority of New York & New Jersey.

According to reports in US media, the route operated from Newark, New Jersey, to Columbia, South Carolina, during a time when United Airlines was lobbying for improvements at Newark Liberty International Airport.

The Port Authority of New York & New Jersey owns Newark Liberty International.

Former Port Authority chairman David Samson owned a vacation home in Columbia at the time.

United said that it was cooperating with investigators.

United launched the twice weekly, direct flight route shortly after Samson was appointed and cancelled it after he left the Port Authority.

United simultaneously announced that it had named Oscar Munoz as president and chief executive officer.

Munoz will also continue to serve on United’s board of directors.

He most recently served as president and chief operating officer of CSX Corporation.

Henry Meyer, non-executive chairman of the board of directors of United Continental Holdings said: “Oscar’s track record demonstrates that he has the right blend of strategic vision and strong leadership to continue United’s upward trajectory.

“United is well positioned to continue executing on its strategic plan to further improve performance and the value and service it provides to its customers.

Munoz has served on the board of directors for United Continental Holdings since 2010 and served on the board of directors of Continental Airlines since 2004.

He is active in several industry coalitions and philanthropic and educational organisations including the University of North Florida’s board of trustees and the PAFA advisory board of Vanderbilt University.

The company also announced that its executive vice president of communications and government affairs and its senior vice president of corporate and government affairs have stepped down.

The departures announced today are in connection with the company’s previously disclosed internal investigation related to the federal investigation associated with the Port Authority of New York and New Jersey.

The investigations are ongoing and the company continues to cooperate with the government.