Donald Trump has sneered at Arnold Schwarzenegger who has replaced him as host of The Celebrity Apprentice, saying the actor had been "destroyed" in TV ratings.
"So much for being a movie star," tweeted the US president-elect, describing himself as a "ratings machine".
Responding to the tweet, cautioned him to work for all Americans "as aggressively as you worked for your ratings".
Monday's season launch of The New Celebrity Apprentice was viewed by an estimated 4.9 million people, a decrease of 43% on the last season premiere in 2015.
In the series, the Austrian-born former governor of California has replaced Trump's "You're fired" catchphrase with "You're terminated," which harks back to to his famous role in The Terminator movies.
In the tweets, sent yesterday, Trump wrote: "Wow, the ratings are in and Arnold Schwarzenegger got "swamped" (or destroyed) by comparison to the ratings machine, DJT. So much for being a movie star - and that was season 1 compared to season 14. Now compare him to my season 1."
Over 11 million people watched the first episode of The Celebrity Apprentice in 2008, as reported by Variety.
Referring to Republican Ohio governor John Kasich and Democratic presidential candidate Hillary Clinton, Trump added: "But who cares, he supported Kasich & Hillary."
In return, Schwarzenegger tweeted: "There's nothing more important than the people's work, @realDonaldTrump."
He also wrote: "I wish you the best of luck and I hope you'll work for ALL of the American people as aggressively as you worked for your ratings."
