Louise Linton, the wife of Treasury Secretary Steve Mnuchin, appeared to side with climate change activist Greta Thunberg – whom her husband had belittled during the World Economic Forum in Davos, Switzerland – in an Instagram post that she then deleted, according to screen grabs of the post shared on social media.

Thunberg, 17, also attended the gathering last week of the world's top political and business leaders, where she called on the world to divest from investments in fossil fuels.

When asked about her demand, Mnuchin quipped, "Is she the chief economist? Who is she? I’m confused."

"After she goes and studies economics in college, she can come back and explain that to us," he added.

"I stand with Greta on this issue. (I don't have a degree in economics either)," the post from his wife's Instagram account read, according to the screen grabs Saturday. "We need to drastically reduce our fossil fuels. Keep up the fight @gretathunberg."

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Though she deleted that post, the actress added another one, titled "Bullies," to her Instagram story in which she responded to harsh criticism of her husband's comments about Thunberg.

"I am not my husband," she wrote. "I happen to love Greta. Whatever he says has nothing to do with my views or opinions and what you just did was bully me, unjustly."

Thunberg also responded to Mnuchin's comments about getting an economics degree.

"My gap year ends in August, but it doesn’t take a college degree in economics to realise that our remaining 1,5° carbon budget and ongoing fossil fuel subsidies and investments don’t add up," Thunberg wrote on Twitter. "So either you tell us how to achieve this mitigation or explain to future generations and those already affected by the climate emergency why we should abandon our climate commitments."

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