The Obama administration is refusing to condemn Israel for its deadly raid on a convoy of ships carrying aid to the Gaza Strip.
Facing reporters' repeated questions at the White House Tuesday, Mr. Obama's spokesman Robert Gibbs said the United States agrees with the wording of a U.N. Security Council statement on the controversial raid.
The Security Council said it "deeply regrets" the casualties that occurred during the Israeli military operation, and it condemned "those acts which resulted in the loss" of life. But the statement does not specifically blame Israel for the bloodshed.
President Obama telephoned Turkish Prime Minister Recep Tayyip Erdogan, who has denounced the Israeli action as a "bloody massacre."
Four Turkish citizens were among the nine people killed when Israeli commandos boarded a flotilla of vessels carrying aid supplies to the Gaza Strip, and Turkey has led the international outcry against Israel for its actions.
Turkey also has called for an independent investigation of the incident - not a probe conducted by Israel. Russia and the European Union issued a joint call Tuesday for an impartial probe, and separately condemned Israel's use of deadly force.
U.S. Secretary of State Hillary Clinton appealed for restraint by all sides Tuesday. She voiced support for an Israeli probe of the assault on the aid convoy, saying any inquiry must be prompt, impartial, credible and transparent, as outlined by the Security Council.
Israel has said its troops fired shots in self defense after they boarded the aid convoy in international waters and encountered resistance.
A White House statement about Mr. Obama's conversation with Prime Minister Erdogan says the president expressed his condolences for Turkey's losses and stressed the importance of finding better ways to provide humanitarian aid to the people of Gaza without undermining Israel's security.
Israeli Prime Minister Benjamin Netanyahu had been scheduled to visit President Barack Obama at the White House Tuesday, but canceled the trip and returned to Israel from Canada.
Palestinian Prime Minister Mahmoud Abbas is expected to meet Mr. Obama at the White House June 9 as scheduled.
Some information for this report was provided by AFP and AP.