Turkish Prime Minister Recep Tayyip Erdogan has told U.S. President Barack Obama that Israel is on the verge of losing its best friend in the Middle East due to its deadly raid on a humanitarian aid headed to the Gaza Strip earlier this week, according to a statement from Erdogan's office.

Obama called Erdogan late Tuesday to express his "deep condolences for the loss of life and injuries" sustained by Turkish citizens during the attack.


The identities of the nine people killed in the raid on Monday have still not been released, but it has widely been assumed that most of them were Turkish.

Reports circulating on Thursday revealed that eight of the fatalities were indeed Turkish citizens, while the ninth held an American passport.

During his telephone conversation with Obama, Erdogan called Israel's raid on the Turkih-flagged an unacceptable violation of international law and norms. He told Obama that he demanded Israel return all Turkish citizens – including the bodies of the fatalities – and said he wanted the aid ships returned. Erdogan also called on Israel to lift the siege on the Gaza Strip.

Obama reiterated during their conversation the United States' support for “a credible, impartial and transparent investigation of the facts surrounding this tragedy," according to the White House.

He also "affirmed the importance of finding better ways to provide humanitarian assistance to the people of Gaza without undermining Israel’s security,” according to the statement.

A once-close ally of Israel, Turkey became a harsh critic after the Israeli offensive in Gaza in December 2008. But the deaths of Turks on in international waters has brought the strained relationship between Israel and Turkey's Islamist-leaning government close to breaking point.

Turkey said on Wednesday it was ready to normalize ties with Israel if it lifted the blockade on Gaza and said "it was time calm replaced anger" in the wake of Israel's deadly raid on a Turkish-backed flotilla.

"The future of ties with Israel will depend on the attitude of Israel," Foreign Minister Ahmet Davutoglu told a news conference in Ankara on Wednesday on his return from the United States. Turkey recalled its ambassador to Israel following Monday's storming of Gaza bound aid ships.

"I see no reason for not normalizing the ties, once the Gaza blockade is lifted and our citizens are released," he added.