(CNN) President Donald Trump's protocol chief, Sean Lawler, has been suspended indefinitely just ahead of the G-20 meeting in Japan pending the outcome of a State Department investigation into his conduct, according to multiple State Department officials with direct knowledge of the matter.

Two State officials told CNN that Lawler was called into the office of the deputy secretary on Monday afternoon and told he needed to leave due to the status of the investigation.

On the same afternoon, senior staff in the protocol office met with State Department management and were told that Lawler had to leave over personnel issues, according to the officials.

They were also told in this meeting that their new acting chief of protocol is Mary-Kate Fisher, and her acting deputy is Cathy Fenton, who served as social secretary in the George W. Bush White House and also handled social affairs‎ for Nancy Reagan and Barbara Bush. State Department sources said both are highly respected.

One of the State Department officials described what multiple others told CNN was a pattern of behavior on Lawler's part. "In my decade of government service, I have never seen someone so unprofessional, abrasive and rude as him," the official said. "His bad behavior was terrible, and it was obvious. I personally saw it myself, as did a good chunk of the office.

Read More