The Arab world's top diplomat declared support Sunday for the people of blockaded Gaza in his first visit to the Palestinian territory since Hamas violently seized control of it three years ago.

The visit was latest sign that Israel's deadly raid on a flotilla trying to break the blockade of Gaza has eased the diplomatic isolation of the Islamic militant group.

Israel, meanwhile, appeared to grow more isolated in the fallout over the May 31 raid as Israeli Defense Minister Ehud Barak abruptly canceled plans Sunday to visit Paris.

Barak's office said he canceled his trip while Israel forms a committee to investigate the raid. The statement denied that the decision was connected to attempts by pro-Palestinian groups to seek his arrest.

Israel said late Sunday it was setting up an inquiry headed by a judge, to be joined by two high-ranking foreign observers.

The government statement said the Israeli Cabinet would be asked to approve the "special independent public commission" on Monday. The chairman is to be Yaakov Turkel, a retired Israeli Supreme Court justice, the statement said. The two foreign observers are to be Lord William David Trimble of Ireland, a Nobel Peace Prize laureate, and retired Brig. Gen. Ken Watkin, the former chief military prosecutor in Canada.

The Obama administration and the U.N. have urged Israel to involve foreigners in the investigation, while Turkey and others have demanded an inquiry without Israeli involvement.

The White House said later it backs Israel's inquiry into the deadly raid, saying the independent public commission is "an important step forward."

Press Secretary Robert Gibbs says Israel's panel can meet the standard of a "prompt, impartial, credible and transparent investigation."

Washington's ambassador to the U.N., Susan Rice, told Fox News on Sunday that while the United States believes Israel can conduct a "credible and impartial" investigation, an "international component" would "buttress its credibility in the eyes of the international community."

Israeli defense officials said Barak called off his trip to Paris over concern about the unwanted attention his visit would attract. In particular, they pointed to the heavy media focus and difficult questions he would face as well as the heightened security arrangements the visit would require. The officials spoke on condition of anonymity because they were not authorized to discuss the matter with the media.

Activists have previously tried unsuccessfully to arrest Barak and other Israeli officials in Europe under the principle of universal jurisdiction.

In another development, several Turkish educators and officials pulled out of an international Holocaust education conference in Israel to protest the raid, organizers said. The raid, which resulted in the deaths of nine Turkish activists, has severely strained ties between former regional and military allies Turkey and Israel.

Arab League chief Amr Moussa's visit to Gaza is part of an international push to end the three-year-old blockade that gained momentum after the naval raid.

"The siege must be lifted," Moussa told reporters. "All the world is now standing with the people of Palestine and the people of Gaza."

It was a significant declaration because many Arab countries have held the Iranian-backed Hamas at arms length, and Egypt, one of the Arab League's most important members, has been Israel's partner in keeping Gaza largely sealed.

Widespread outrage in the Arab and Muslim world over the raid has prompted Arab leaders to join the growing international demands for opening Gaza's borders. In a first step, Egypt has eased the very limited travel at its Rafah crossing with Gaza.

Israel says the blockade is necessary to stop weapons reaching Hamas, but critics say it has failed to dent support for the Islamic militants and has left 1.5 million Gazans more deeply mired in poverty.

Moussa was the first senior Arab official to visit Gaza since the territory came under the control of Hamas, which much of the West considers a terrorist organization.

The head of the 22-member Arab League met Sunday with the top Hamas leader in Gaza, Prime Minister Ismail Haniyeh, in a significant diplomatic boost for Hamas. The meeting took place in Haniyeh's home in Gaza's Shati refugee camp, and the men later walked around the neighborhood for 10 minutes.

"The acrimony between Gaza and the Arab nation ended today and forever," said Bassem Naim, a Hamas Cabinet minister who greeted Moussa.

Moussa said Gaza reconstruction projects are ready, but there must be a "national unity approach" for them to be implemented, a reference to the split between Hamas in Gaza and Western-backed Palestinian President Mahmoud Abbas in the West Bank.

As part of the border blockade, Israel restricts imports to Gaza, only permitting a few dozen types of foods and medicines, while barring raw materials, including construction supplies. Virtually all exports are banned.

As a result, more than 70 percent of Gaza's 3,900 factories and workshops stand idle or operate at minimal capacity, and tens of thousands have lost their jobs. U.N. officials say 80 percent of Gazans now receive some type of aid.

In Jerusalem, Israeli Prime Minister Benjamin Netanyahu reiterated to his Cabinet Sunday that Israel must maintain the blockade to prevent weapons and goods that could be used for military purposes from reaching Hamas. The Islamic group has fired thousands of rockets at Israel.

"The principle guiding our policy is clear — to prevent the entry of war materiel from entering Gaza and to allow the entry of humanitarian aid and non-contraband goods into the Gaza Strip," Netanyahu said.

President Barack Obama said last week that the blockade in its current form is unsustainable.