Former New Jersey Gov. Chris Christie is among the candidates who could serve as White House chief of staff, with one source calling him a "strong option" for the job.

CNN reporter Shimon Prokupecz tweeted this Monday afternoon in regard to the post that will soon be vacated by John Kelly:

"A source close to the WH says former NJ gov Chris Christie is also under consideration for Chief of Staff. The source said Christie is considered a 'strong option' a this point, adding Trump wants 'a functioning White House.'"

In a separate piece of reporting, CNN's Jim Acosta quoted a source close to President Donald Trump as saying the president is "super pissed" he has to restart his chief of staff search after Nick Ayers, currently Vice President Mike Pence's chief of staff, turned it down.

Reuters reported Monday that Rep. Mark Meadows, R-N.C., former Trump campaign adviser David Bossie, and U.S. Trade Representative Robert Lighthizer are also being considered for the chief of staff job.

The search comes after Ayers, Trump's initial choice for the job, bowed out Sunday. He announced his resignation as Pence's chief of staff and said he will leave the administration at the end of the year.

Trump announced Saturday that Kelly would also depart at the end of December. The two men had clashed for months.

Material from Reuters was used in this report.