White House Communications Director Steven Cheung got into a war of words on X with a staffer for Sen. Mark Warner (D-Va.) — and ended the exchange by angrily using the R-word.

The online clash began Tuesday when Cheung took exception to Rachel Cohen, communications director for Warner, for questioning why CNN was interviewing Tricia McLaughlin.

Cohen called McLaughlin, a former Department of Homeland Security spokesperson and Trump ally, “easily the most mendacious spokesperson I’ve had the displeasure of encountering in 15 years of doing this.”

“What could she POSSIBLY have to say that adds to viewers’ understanding of anything??” she added.

Cheung quote-posted Cohen’s comments and responded:

“Don’t be jealous you’ll never get booked on TV because you’re a loser.”

He praised McLaughlin as “one of the best communicators around” and suggested Cohen “can learn a thing or two from her.”

“But you won’t because, again, you’re a loser,” he added.

Cohen fired back, writing:

“Hey Steven, remember the time you were so bad at your job the West Wing called to ask us to intervene with the media to protect national security? Because you couldn’t get it done? I was told you were the one handling that story. I’d be happy to teach you how to do it next time!”

“Hey retard, you must be thinking of someone else. Nobody would ask your simple ass for help.”

Cheung has a long history of using Trump-style attacks against the president’s critics and members of the media, including HuffPost’s own S.V. Date, who ask questions he doesn’t want to answer.

Meanwhile, Donald Trump himself has used the R-word slur on multiple occasions.