After Donald Trump referenced one of Game of Thrones' most popular catchphrases — winter is coming — in a tweet revealing U.S. sanctions against Iran, stars of the HBO show are speaking out against the president on Twitter

'Ew': Sophie Turner, Maisie Williams and More Slam Trump for Game of Thrones-Inspired Tweet

After Donald Trump referenced one of Game of Thrones‘ most popular catchphrases — winter is coming — in a tweet revealing U.S. sanctions against Iran, stars of the HBO show are speaking out against the president on Twitter.

Maisie Williams, 21, who plays Arya Stark on the hit show, tweeted, “Not today.”

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And Sophie Turner, 22, who plays her sister Sansa Stark, simply tweeted, “Ew.”

HBO also voiced its disapproval over the tweet, saying in a statement obtained by PEOPLE, “We were not aware of this messaging and would prefer our trademark not be misappropriated for political purposes.”

The White House did not immediately respond to PEOPLE’s request for comment on the tweet and HBO’s statement.

The network also poked fun of Trump’s tweet on Twitter, writing, “How do you say trademark misuse in Dothraki?” a reference to the language spoken by the nomadic warriors who roam the series’ Dothraki sea.

Game of Thrones creator George R.R. Martin also reacted on Twitter, tweeting directly at Trump an image that read: “Fear cuts deeper than swords. Vote Tuesday the 6th.”

On Friday, Trump tweeted an image of himself which featured a text overlay that read, “Sanctions are coming,” an apparent play on the much-memed Game of Thrones slogan. The font of the text also appears to mimic that used in the HBO series.

The White House Twitter account followed up Trump’s tweet with an announcement that the president is reimposing all sanctions lifted under the Iran deal, which was negotiated by then-President Barack Obama and five other world powers in 2015 in an effort to restrict Iran’s ability to develop nuclear weapons.

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