President Donald Trump's namesake, Donald Tusk, president of the European Council from 2014 to 2019, should watch where he points his hands the next time he's around Trump.

For some strange reason, the Polish politician and a long-time Trump critic on Thursday tweeted a photo of himself pointing a pair of fingers at Trump’s back during the just concluded NATO summit in London. Trump walked-out of the summit after what he thought were personal slights against him by some of the other heads of state.

Tusk tweeted this photo from his personal account to his 6,800 followers with a message of transatlantic unity. Tusk captioned the photo: “Despite seasonal turbulences our transatlantic friendship must last #Trump #NATO."

In the United States, this gesture is a "hand gun" sign suggesting firing a gun at a person. That's a felony in Philadephia where "imitating the firing and recoiling of a gun" with one's fingers is intimidation. It's considered a "crime of disorderly conduct."

Tusk, who was also prime minister of Poland from 2007 to 2014, didn't explain why he pointed two fingers at Trump given its menacing undertones, which partly explains the anger of right-wingers on social media.

The backlash on social media to this case of naughty fingers was immediate and painful for Tusk. Tusk's countrymen were both apologetic and enraged at Tusk's faux pas.

One user tweeted "Gówniarz, a nie mąż stanu!" which translates to "S--t, not statesman."

Another wrote, “As a Polish citizen I am embarrassed for this person." A person identifying himeself as @MikiPoznan tweeted, “Dear @realDonaldTrump, Poland apologizes for Donald Tusk."

Some Trump supporters also voiced out their disgust on the gesture.

Another user added, "I hope this is mistaken, otherwise Maybe we should remove our defense system from Poland and let them speak Russian, I’m sure Putin would like control there."

There is no love lost between the two Dons. In his final speech to the United Nations General Assembly in New York this September, Tusk called Trump's views on patriotism “false and dangerous.”

“To protect the truth, it is not enough to accuse others of promoting fake news,” he said. “Frankly speaking, it would be enough to stop lying.”

European Council President Donald Tusk said he would begin consulting EU leaders 'on how to react' - a process one diplomat said could take a few days
European Council President Donald Tusk said he would begin consulting EU leaders 'on how to react' - a process one diplomat said could take a few days AFP / Aris OIKONOMOU