The White House said Friday President Barack Obama asked Turkish Prime Minister Recep Tayyip Erdogan to speak out against anti-American attacks in Arab countries and the YouTube movie that sparked them.
Erdogan followed through on Obama's request, saying in Ukraine on Friday that the film was a provocation but should not be used as a pretext for violence.
Obama has built a close relationship with Erdogan, and White House officials view him as one of the US leader's most important foreign allies.
White House spokesman Jay Carney noted that Obama "sent a message -- a personal message -- to the leader of Turkey, Prime Minister Erdogan, asking for his assistance to speak out against the violence."
Carney said the president had also called the leaders of Egypt and Libya to ask for their help in protecting American diplomats and installations.
"And I think you saw that the prime minister did that, and the president is very appreciative of these statements and the actions these leaders have taken personally."
Erdogan said in a speech in Yalta that the movie, extracts of which are up on YouTube, "was a strong provocation against our way of life."
"Insulting the prophet cannot be justified as freedom of expression. Religion and the prophet are sacred values and are untouchable."
He added: "Legal and peaceful protest by Muslims is a useful and correct thing," but "it cannot be a reason for innocent people to be attacked or harmed.
"This is justified by nothing and above all not by Islam. No one can, in the name of Islam, carry out actions of the kind that happened in Libya with the attack on the US mission" in Benghazi," he said.
Also on Friday, Egypt's powerful Muslim Brotherhood withdrew its calls for nationwide protests, saying they would instead participate in a "symbolic" demonstration "so that there is no more destruction to property, or injuries, or deaths."
US and Libyan officials are probing the attack on the US consulate in Libya that killed the ambassador and three other US officials, amid growing speculation it was the work of militants rather than demonstrators.