Swedish climate activist Greta Thunberg speaks to participants at a climate change protest on January 17, 2020 in Lausanne, Switzerland. The protest is taking place ahead of the upcoming annual gathering of world leaders at the Davos World Economic Forum.

Louise Linton, the wife of Treasury Secretary Steve Mnuchin, deleted a post on Instagram on Saturday in which she had expressed support for the teenage climate activist Greta Thunberg, who has been publicly sparring with Mnuchin over whether the U.S. should divest from fossil fuels.

Mnuchin had dismissed the Swedish activist's call for the U.S. to divest from the sector on Thursday, saying that the 17-year-old should study economics in college, and then "she can come back and explain that to us."

Thunberg had called for the divestment at the start of the World Economic Forum in Davos, Switzerland. Her address followed the hottest year on record for the world's oceans, and the second hottest year on record for global average temperatures.

Linton wrote in her post, which tagged both Thunberg and Mnuchin, that she was sympathetic to Thunberg.