JERUSALEM — Turkey expelled Israel's ambassador Friday and downgraded ties to the lowest possible level over Israel's refusal to apologize for a raid on a Gaza-bound flotilla that killed nine people last year.

Turkey's announcement came as details were leaked over an anticipated U.N. report on the flotilla. The report concluded that Israel used "excessive and unreasonable" force on board the Turkish ship Mavi Marmara, leading to the deaths of nine Turkish nationals. The ship was part of a flotilla that was attempting to reach Gaza and draw attention to Israel's ongoing blockade there.

The U.N. report condoned Israel's blockade as a "legitimate security measure," angering pro-Palestinian supporters, who contend that the Gaza Strip has been under siege for years.

Turkish President Abdullah Gul joined Arab leaders across the region in condemning the U.N. report.

"To be frank, the report is null and void for us," Gul said.

Turkish Foreign Minister Ahmet Davutoglu said the government was downgrading diplomatic ties with Israel and that the ambassador and other high-level diplomats would leave the country by Wednesday.

In other measures, Davutoglu said, Turkey would back flotilla victims' families' court actions against Israel and take steps to ensure "free navigation" in the eastern Mediterranean

"The time has come for Israel to pay for its stance that sees it above international laws and disregards human conscience," Davutoglu said. "The first and foremost result is that Israel is going to be devoid of Turkey's friendship."

Davutoglu said the report "displayed the violence committed by the Israeli soldiers," but he also criticized it for describing Israel's naval blockade as a legitimate security measure and in line with international law.

"Turkey does not recognize Israel's embargo on Gaza," Davutoglu said, adding that Turkey would take steps to have the International Court of Justice and the United Nations look into its legality.

An Israeli official from the Foreign Ministry said Israel's actions were in accordance with international law. He spoke only on the condition of anonymity because he wasn't authorized to speak until the U.N. report is released officially.

"The U.N. report should clarify that Israel's actions in Gaza are legitimate. The flotilla tried to embarrass Israel. This did not work," he said.

International attention turned toward Gaza after the deaths on board the Mavi Marmara. Amid an international outcry, Israel loosened its blockade on Gaza and allowed a larger variety of foodstuffs in Gaza.

Relations between Turkey and Israel, however, haven't recovered. Several attempts to reconcile the once-strong allies were met with limited success. U.S. mediators managed to convince Turkey to pull out of a second Gaza-bound flotilla attempt this summer, but they were unable to reach a compromise on the wording of an apology from Israel.

Israel's hard-line foreign minister, Avigdor Lieberman, was said to be a key stumbling point in the negotiations.

Lieberman said an apology would be seen as a "sign of weakness"

"Whoever sees the positions expressed by Turkey" — regarding Israel and the Palestinians — "in the international community does not have any illusions that an apology will dramatically improve Israel's ties with Turkey," he said. "When you apologize it is seen as a sign of weakness."