Two teachers union leaders posted a photo on Twitter expressing their solidarity with the Ukrainian people amid Russia's invasion, but they made an elementary mistake – and some critics say the social media post serves as an advertisement for school choice.

"AFT President [Randi Weingarten] and [AFT Executive Vice President Evelyn DeJesus] stand with #Ukraine," the American Federation of Teachers (AFT) Twitter account posted on Tuesday. The tweet included a photo of Weingarten and DeJesus holding a poster supporting Ukraine.

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The education leaders only had one minor problem – the Ukraine flag in their poster was upside down.

(Twitter screenshot)

Ukraine's flag features blue on top of yellow – symbolizing the blue sky over a bountiful field. 

Ukraine flag

Ukraine flag (iStock)

Critics savaged the teachers union leaders on Twitter.

Corey DeAngelis, national director of research at School Choice Now, called the tweet "free advertising for school choice."

"They did to that flag what they did to education these past two years… pretend they care, but really, they just made it upside down," Reopen California Schools tweeted.

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"That’s the flag of Ukraine alright, upside down," California State Senator Melissa Menendez tweeted. "Shout out to the teachers union for this promotional piece on the importance of school choice though."

Teachers unions have faced hefty criticism after many of them supported the closure of schools during the COVID-19 pandemic, and pushed back against reopening. Teachers have also raised concerns about socially-liberal activism in the classroom and in teacher trainings, regarding such issues as critical race theory and transgender identity.

Sen. Ted Cruz, R-Texas, pointed out that "They actually printed this sign…with the flag upside down!"

The poster reads, "We stand with Ukraine, AFL-CIO." 

The AFL-CIO posted a photo of its leaders with multiple such signs – all with the flag upside down.

(Twitter screenshot)

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The AFL-CIO appeared to recognize its mistake, later tweeting the same image and message, but with the flags digitally altered to appear right-side-up.