The flap erupted after US treasury secretary Steven Mnuchin's wife, Scottish-born actress Louise Linton, posted a photo of herself emerging from an aircraft in Kentucky wearing a white outfit and sunglasses, using the hashtags "#tomford," "#hermesscarf" and "#valentino," according to images of the Monday evening post on social media.
In her initially vitriolic response to being criticised as "deplorable", Linton had lashed out about how much she and her husband contribute to the economy and pay in taxes.
Louise Linton's post on Instagram Source: Instagram
"Do you think the US govt paid for our honeymoon or personal travel?! Lololol," she said, according to images of the response posted online. "Have you given more to the economy than me and my husband? Either as an individual earner in taxes OR in self sacrifice to your country? I'm pretty sure we paid more taxes toward our day 'trip' than you did."
On Tuesday, she scrolled back.
"I apologize for my post on social media yesterday as well as my response. It was inappropriate and highly insensitive," Linton said in a statement released through a publicist.
Linton has since made her Instagram account private.
Jenni Miller, who identified herself as a mother of three from Portland, Oregon, had said of Linton's original post on Instagram: "Glad we could pay for your little getaway. #deplorable."
The US Treasury did not respond to requests for comment.
The high-end fashions Linton called out in her post carry hefty price tags, with Hermes scarves retailing from $300 to more than $2,300.
Mnuchin is a former Goldman Sachs Group Inc executive and Hollywood film financier.
Linton has been at the center of controversy before. Last year she withdrew a self-published book in which she claimed to have been caught up in violence in Zambia. African leaders and aid workers said the book was filled with factual errors.
