U.S. President Donald Trump (L) poses with outgoing White House Communications Director Hope Hicks on the West Wing Colonnade before departing from the White House in Washington D.C., the United States, on March 29, 2018. (Xinhua/Ting Shen)

WASHINGTON, March 29 (Xinhua) -- U.S. President Donald Trump bid farewell on Thursday to one of his closest and longest-serving aides, Communications Director Hope Hicks.

The president appeared alongside Hicks in front of cameras outside the Oval Office on her last day at the White House. After waving to the cameras, Trump gave Hicks a handshake and a kiss on the cheek.

Hicks announced her resignation in late February after the White House was consumed by controversy over allegations of domestic violence by then-Staff Secretary Rob Porter from two ex-wives.

Porter, who has denied those allegations, was at that time romantically involved with Hicks who helped draft the administration's initial statements to support Porter, according to U.S. news network CNN.

Ultimately, Porter left his job, while both Hicks and the White House were caught in a communications storm. But senior officials disputed that Hick's decision to leave the West Wing was related to the incident.

In addition, investigators have sought to determine what Hicks knew about Trump's decision to fire Director of Federal Bureau of Investigation James Comey and the alleged Russian meddling in the 2016 general elections.

Testifying before a closed session of the House Intelligence Committee weeks after Porter's resignation, Hicks said her job sometimes requires her to tell "white lies" on behalf of the president, New York Times daily reported.

Hicks had worked with Trump before he announced his candidacy, through the campaign and into the second year of the administration.

Her role evolved from what was initially considered to be an unconventional press and communications aide to formally being announced the White House communications director in the summer of 2017.

"She is as smart and thoughtful as they come, a truly great person," Trump said in a statement accepting Hicks' resignation, and "I will miss having her by my side."

There is no immediate successor to Hicks' post. White House officials did not rule out the possibility of Hicks returning to the administration at some point in the future.