President Trump on Friday referenced the popular HBO series Game of Thrones in a tweet announcing the reimposition of sanctions on Iran. “SANCTIONS ARE COMING NOVEMBER 5,” reads the tweet, which includes an image of a stern-looking Trump. The post is a reference to “Winter is Coming,” the motto of the show’s fictional Stark family. In a statement to CNBC, HBO said that it was “not aware of this messaging and would prefer [its] trademark not be misappropriated for political purposes.” The network also tweeted, “How do you say trademark misuse in Dothraki?” Actress Maisie Williams, who plays Arya Stark in the series, responded with a tweet reading: “Not today.” Sophie Turner, who plays Sansa Stark, simply wrote “Ew” in response. Trump’s tweet was posted shortly after officials announced that sanctions against Iran would be reimposed on Monday. The sanctions were reportedly lifted by former president Barack Obama as part of the 2015 Iran nuclear deal.