Reports by Israel's two main radio stations said US Secretary of State Hillary Clinton called Prime Minister Benjamin Netanyahu on Tuesday with a direct request that he make an apology, but he turned her down.
"He said Israel has no intention of apologizing at this time and that he is waiting for the publication of a report by the UN secretary-general," army radio said.
A United Nations report into the flotilla affair, whose publication has been postponed at least twice this year to allow time for the two sides to reconcile their differences, is due to be released on Aug. 22.
Israeli officials, citing advance copies of the report, have said it would vindicate Israel's blockade on the Hamas-ruled Gaza Strip. Turkey, which like Israel had a delegate on the UN panel headed by former New Zealand Prime Minister Geoffrey Palmer, has said it would not accept such a finding.
Netanyahu has voiced regret over the killings. But Turkey insisted on a formal apology and compensation for those bereaved and injured, which Israel initially rejected as tantamount to admitting culpability for an action it deems self-defense.
Defense Minister Ehud Barak, a centrist in Netanyahu's conservative coalition government, has since stirred debate inside the Cabinet by proposing Israel offer a diluted apology in hope of restoring ties with what was once a rare Muslim ally of the Jewish state.
In arguing for accommodating the Turks, Barak had said this would help indemnify Israel's Navy personnel against lawsuits abroad. The Palmer report would contain some criticism of Israeli tactics aboard the Mavi Marmara, Barak said.
His most vocal opponent in the Israeli Cabinet was Foreign Minister Avigdor Lieberman, who noted that Ankara's government also demands an end to the Gaza blockade.
Israeli daily Yediot Aharonot earlier reported that Israeli diplomats in Washington had passed on a message from Clinton saying the Israel-Turkey crisis was interfering with US attempts to deal with the bloodshed in Syria.
A similar message was given to Barak when he visited Washington in late July, when Clinton asked him to do everything in his power to resolve the crisis — "including tendering an apology," the paper said.
Turkey recalled its ambassador from Tel Aviv immediately after the May 2010 Israeli commando raid on the Turkish ferry. Israel has steadfastly refused to apologize, although privately officials acknowledge that restoring the once-strong relationship with Ankara would be desirable.
The United States is looking to deepen its ties with Turkey, which shares a border with Syria, in a bid to better handle Syria's spiraling violence, and hopes an Israeli apology would facilitate that, the Yediot said.
Kurt Hoyer, spokesman for the US Embassy, said Washington wanted Israel and Turkey "to look for opportunities to get past the current strains in their bilateral relations." He would not comment on the conversation on Tuesday's conversation between Netanyahu and Clinton.
Responding to the reports, Turkish Prime Minister Recep Tayyip Erdogan said on Wednesday it would be impossible for Turkish-Israeli ties to improve unless Israel apologized and paid compensation for the killing of the Turks aboard the Gaza-bound ship.
