(CNN) -- The political repercussions of Israel's raid of boats carrying aid to Gaza last week continued to ripple across the Middle East and showed no signs of slowing Tuesday.
Speaking to reporters outside an Asian security summit in Istanbul, Turkey, Iranian President Mahmoud Ahmadinejad said the killing of nine Turkish activists by Israeli naval commandos aboard one vessel in the flotilla "will change many issues in the world" and marked the "final countdown" for Israel's existence.
"It shows that it has no room in the region, and no one is ready to live alongside it," he told reporters.
His comments came as more aid ships, some backed by regional powers, prepared to set sail.
Israel has said its naval blockade is in place to stop weaponry from reaching militants in Gaza intent on attacking Israel. But critics say the three-year blockade -- imposed after Hamas took over Gaza -- has deepened poverty in the Palestinian territory.
According to the United Nations, 80 percent of Gaza's population depends on food aid.
Iran's Foreign Ministry said Monday that the country's Red Crescent Society would also try to break the Israeli blockade of Gaza by sending food and medical supplies to the besieged Palestinian territory, according to Iranian media. Red Crescent official Abdul Rauf Adibzadeh told Iranian media one shipment of relief goods would arrive in Gaza via Egypt by the end of the week.
Separately, a "Jewish boat" is planning to try to reach Gaza, two pro-Palestinian European Jewish groups announced Monday.
"Our purpose is to call an end to the siege of Gaza, to this illegal collective punishment of the whole civilian population," Edith Lutz said on behalf of European Jews for a Just Peace in the Near East, and Jews for Justice for Palestinians.
Meanwhile, thousands of tons of international aid, meant for Gaza but seized by Israel at sea, are languishing in an army base close to Tel Aviv. Wheel chairs and children's toys are among the goods.
Israel has screened the aid for banned materials, and is offering to transport the rest to Gaza by land.
But Hamas, the militant group which runs the territory, is refusing to take delivery in protest.
Israeli commandos intercepted the first convoy at sea May 31 and stormed the largest vessel, the Turkish-flagged Mavi Marmara.
On Saturday the Israeli military seized the MV Rachel Corrie, another aid ship, as it neared the Gaza coast.
The ships were carrying humanitarian aid to Gaza, organizers said.
U.S. Vice President Joe Biden said Monday that the present situation "is unsustainable for all sides," and that the Israelis and Palestinians needed to "move to direct negotiations as soon as possible that will result in an end to the occupation that began in 1967, and to a two-state solution to the conflict with Israel, and a Palestinian state living in peace and security."
The U.N. Security Council has called for an inquiry into the flotilla raid, and the U.N. Human Rights Council has condemned the assault and voted to launch an investigation.
Israeli officials have defended the legality of the raid, criticizing those aboard the Mavi Marmara for attacking the boarding party and insisting that they can handle the investigation themselves.
On Monday the Israeli military's chief of general staff has appointed a reserve general to lead "a team of experts" to examine Israel's interception of a flotilla bound for Gaza last week in order to "establish lessons from the event," the Israel Defense Forces said in a statement.
CNN's Matthew Chance and Reza Sayah contributed to this report.