White House Communications Director Hope Hicks, one of President Donald Trump's longest-serving advisers, announced her resignation Wednesday.

Hicks, 29, has been a longtime member of the Trump family's inner circle, and worked as press secretary for his presidential campaign before being chosen to join the White House staff. The sudden announcement of her resignation yielded mixed reactions on the internet by White House staffers and other social media users.

The former model previously worked for the Trump Organization and also for first daughter Ivanka Trump's fashion brand. Hicks, who was the fourth communications director since Trump became president, reportedly told her colleagues she felt she accomplished all she could in the White House.

The news of her resignation was first reported by the New York Times and it came a day after she appeared before the House Intelligence Committee, which was investigating Russian meddling in the 2016 election, and admitted to the panel she occasionally tells "white lies" for the president, according to lawmakers. However, Hicks denied lying about anything relevant to the investigation into the Russian interference in the 2016 presidential election.

In a statement, the former White House communications chief said she had "no words" to express "gratitude" to the president, adding, "I wish the President and his administration the very best as he continues to lead our country." 

According to an unnamed White House official, Hicks informed Trump of her decision to resign earlier Wednesday, in person.

Trump responded to her resignation in a statement praising Hicks for her service.

"Hope is outstanding and has done great work for the last three years. She is as smart and thoughtful as they come, a truly great person," the president said. "I will miss having her by my side but when she approached me about pursuing other opportunities, I totally understood. I am sure we will work together again in the future."

Hope Hicks Former White House Communications Director and presidential adviser Hope Hicks (C) arrives at the U.S. Capitol Visitors Center in Washington, D.C., Feb. 27, 2018. Photo: Getty Images

Hicks' exact departure date is yet to be fixed; however, it is likely to be sometime in the next few weeks. Officials from the White House said Hicks reportedly wanted to pursue new opportunities outside.

Top White House staffers, including Press Secretary Sarah Sanders and counselor to the president Kellyanne Conway, were apparently caught off guard by Hicks' abrupt resignation Wednesday afternoon.

"There is no one that can fill the void Hope Hicks will leave behind," Sanders tweeted. "She is in a league of her own and no one can replace her. Far and away one of the most talented and skilled people I’ve ever met and coming to work won’t be the same without her."

Conway’s response was much briefer:

Ivanka also tweeted about Hicks' resignation and wished her well in "her next steps."

Other social media users had mixed reactions to Hicks' sudden departure.

It was not immediately determined who will replace Hicks as White House communications director. However, some of Hicks’ duties have mostly been filled over the last two months by Mercedes Schlapp, who is the senior adviser for strategic communications, according to CNN.