Israel's Cabinet on Monday approved an investigation into the navy's deadly raid on a flotilla carrying pro-Palestinian activists bound for blockaded Gaza that will include two respected foreign observers in a step aimed at countering worldwide criticism of the operation.

Israel has been under heavy pressure to carry out an impartial inquiry into the events of May 31, when naval commandos clashed with activists on board a Turkish ship headed to Gaza. Nine Turkish activists were killed, and dozens of people, including seven soldiers, were wounded.

Israel has rejected calls for an international investigation, saying the United Nations and other global bodies have a long history of bias against the Jewish state.

But in consultation with its key ally, the United States, Israel agreed to add two high-ranking foreign observers to bolster the credibility of the probe: David Trimble, a Nobel peace laureate from Northern Ireland, and Canada's former chief military prosecutor, retired Brig. Gen. Ken Watkin.

Trimble is a member of a pro-Israel faction in Britain's House of Lords. Watkin has been a visiting fellow in the human rights program at Harvard Law School.

Before Monday's Cabinet vote, Prime Minister Benjamin Netanyahu said he was confident the makeup of the commission would blunt the international criticism and prove Israel handled the affair responsibly.

"I am convinced that the commission's uncovering of the facts will prove that the goals and actions of the state of Israel and the Israeli military were appropriate defensive actions in accordance with the highest international standards," he said.

The White House has backed Israel's inquiry into the raid, calling it "an important step forward."

The naval commandos clashed with the activists after landing on the deck of the Turkish ship from helicopters.

Israel says the ship was carrying dozens of trained militants who had prepared to confront the soldiers. It has released videos showing the activists attacking the soldiers with clubs, metal pipes and knives.

The activists say they were only defending themselves, and some members of the international community, particularly Turkey, have accused Israel of using excessive force and acting illegally in international waters.

There was no immediate international reaction to Monday's Cabinet decision.