"This ambassador, who everybody says was so wonderful," Mr Trump said, "she wouldn't hang my picture in the embassy.
"She's in charge of the embassy, it took, like, a year and a half, two years."
He added that his personal lawyer, Rudy Giuliani, "didn't say good things" about her.
"She said bad things about me, she wouldn't defend me, and I have the right to change the ambassador," Mr Trump added.
"The standard is you put the president of the United States' picture in the embassy," he continued. "This was not an angel, this woman, OK?"