Turkey's move came before the anticipated publication Friday of a U.N. report on violence aboard a Gaza-bound protest flotilla. The fatalities included eight Turkish nationals and one Turkish-American activist.

The report, obtained by The New York Times and posted on its website, said Israel's naval blockade of Gaza is a "legitimate security measure." But it also said Israel's use of force against the flotilla was "excessive and unreasonable," according to the newspaper.

An Israeli official said the report showed Israel's naval blockade was in keeping with international law. He spoke on condition of anonymity because the report had yet to be officially released. He said Israel expected it to be made public by the U.N. later Friday.

Turkey has made an Israeli apology a condition of improving diplomatic ties. Israeli officials say the report does not demand an Israeli apology, establishing instead that Israel should express regret and pay reparations.

Turkish Foreign Minister Ahmet Davutoglu said the government was downgrading diplomatic ties with Israel to the level of second secretary and that the ambassador and other high-level diplomats would leave the capital Ankara by Wednesday.