JERUSALEM -- Israel announced Monday it will take part in a U.N. investigation into the deadly Israeli raid on a Gaza-bound flotilla last spring, in a departure from its traditional mistrust of the world body.

The move allowed U.N. head Ban Ki-moon to formally announce the creation of an investigation panel into the incident in which nine Turkish activists, including one with U.S. citizenship, died after being shot by Israeli commandos boarding their ship.

"I sincerely hope that this will contribute to the peace process as well as improvement of relationship between Israel and Turkey," Ban said. The panel will include both Turkish and Israeli representatives.

The flotilla had been trying to breach Israel's three-year blockade of the Gaza Strip. Both sides have said they were acting in self-defense during the confrontation, which has strained relations between Turkey and Israel.

"Israel has nothing to hide. The opposite is true. It is in Israel's national interest to ensure that the factual truth about the entire flotilla incident will be brought to light and the entire world, and that is precisely the principle we are promoting," Prime Minister Benjamin Netanyahu said in a statement.

Government spokesman Mark Regev would not say what, if any, assurances Israel had received from the U.N. chief.

At U.N. headquarters, Ban said the investigation panel will be co-chaired by former New Zealand Prime Minister Geoffrey Palmer and outgoing Colombian President Alvaro Uribe. He did not identify the Israeli and Turkish members.

The deal was reached after what Ban described as two months of "intensive consultation with the leaders of Israel and Turkey," and last minute talks over the weekend. He thanked both leaders "for their spirit of compromise and forward looking attitude."

The U.N. chief said the panel will start work on Aug. 10 and submit its first progress report by mid-September.

Ban expressed hope that the panel would meet the U.N. Security Council's call on June 1 for a "prompt, impartial, credible and transparent investigation conforming to international standards."

The decision marks a departure for Israel, which has frequently viewed the United Nations with suspicion and accused many U.N. bodies of being unfairly biased against the Jewish state.

Israel refused to cooperate with an earlier investigation into last year's war in the Gaza Strip conducted by the U.N. Human Rights Council, which it accuses of disproportionately focusing on Israel. That council's probe concluded that Israel and Gaza's militant Hamas rulers both committed war crimes.

The statement from Netanyahu's office said Israel relayed its consent "after political contacts that took place in the past few weeks with the objective of ensuring that the panel and its written mandate will be balanced and fair."

There was no immediate reaction from Turkey, which withdrew its ambassador and scaled back relations with Israel following the flotilla incident.

Turkey has said it would not repair relations until Israel agreed to an international investigation.

Israel imposed its blockade of the Gaza Strip after Hamas militants seized power there three years ago. Israel has said the measures were needed to prevent Hamas from arming, but the blockade has brought Gaza's economy to a virtual standstill. Under heavy international pressure, Israel has eased the blockade since the outcry following the flotilla raid.

Israel is conducting a separate investigation into the legality of the Israeli naval blockade on Gaza and the military's actions in enforcing it.

An Israeli military probe criticized flawed intelligence gathering and planning in confronting the flotilla, but stated there was no wrongdoing on the part of the soldiers.