President Donald Trump on Wednesday complained about purportedly being treated poorly by the Danish government for its refusal to sell him Greenland.

As PBS News’ Yamiche Alcindor reports, Trump told reporters that he was upset at the way Danish Prime Minister Mette Frederiksen has handled his overtures to purchase Greenland.

“I thought it was a very not nice way of saying I can’t buy Greenland,” the president complained, according to Alcindor. “They could have just told me no. You don’t talk to the United States like that at least under me.”

Trump’s tantrum at a staunch American ally earned him instant ridicule on Twitter — check out some of the reactions below.