The American Eagle ad, which features the 27-year-old actress, who starred in the HBO series Euphoria and White Lotus, has the tagline “Sydney Sweeney has great jeans”.
It has sparked a debate in the US over race and Western beauty standards.
In a since-corrected Truth Social post, the US president initially misspelt Sweeney’s first name, saying: “It’s for American Eagle, and the jeans are ‘flying of the shelves.’ Go get ’em Sidney.”
Most of the criticism has centred on videos using the word “genes” instead of “jeans”, with one in which Sweeney says: “Genes are passed down from parents to offspring, often determining traits like hair colour, personality and even eye colour. My jeans are blue.”
Critics argued the play on words potentially promotes eugenics, a discredited theory that believed humanity could be improved through the selective breeding of certain traits.
But others have defended the ad, saying the critics are reading too much into its message.
The video appeared on American Eagle’s Facebook page and other social media channels, but is not part of the ad campaign.
In a statement on Instagram on Friday, American Eagle Outfitters said the campaign “is and always was about the jeans. Her jeans. Her story. We’ll continue to celebrate how everyone wears their AE jeans with confidence, their way. Great jeans look good on everyone.”
Stocks in American Eagle Outfitters jumped by 23.3% after Mr Trump’s intervention.
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In his Truth Social post, which he reposted three times to fix various typos, Mr Trump compared the ad with “woke” ones “on the other side of the ledger” – as he criticised other companies, as well as hitting out at Taylor Swift.
“The tide has seriously turned – Being WOKE is for losers, being Republican is what you want to be,” he wrote.
Sky News has contacted Sweeney’s agent for comment.
