The two politicians met on Wednesday night for dinner at Trump Tower in Manhattan.
Although Duda was accompanied by his aides, Marcin Mastalerek and Wojciech Kolarski, he said the nature of the meeting was private.
"It was a friendly meeting in a nice atmosphere," Duda said after the supper.
Right before the meeting, Trump said that his relationship with Duda was a personal one and he referred to their cooperation from his time in the White House.
"He's doing a fantastic job. The people of Poland love him, they really do," he said.
"He's my friend, and we had four great years together."
He added: "We're behind Poland all the way."
A similar sentiment was conveyed by Kolarski, who said: "It was an excellent meeting. The conversation lasted over two hours and passed in a great atmosphere. It was a meeting of two friends." (PAP)
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