The International Atomic Energy Agency (IAEA) says it will open an investigation into Israel's alleged use of depleted uranium during the 22-day offensive in the Gaza Strip.
Wednesday's announcement came after Arab nations sent a letter to Mohammed ElBaradei, the IAEA director-general, asking the UN agency to investigate whether the controversial munitions were used in the war, which left more than 1,300 Palestinians dead.
Depleted uranium is added to munitions because its density allows them to penetrate armor more easily.
It is thought that the dust left at blast sites after the weapons have hit could pose a health risk, but a definitive link has not yet been proven.
"We are circulating the letter to member states and will investigate the matter to the extent of our ability," Melissa Fleming, an IAEA spokeswoman, said after the UN agency received the letter from the Saudi Arabian ambassador.
The exact course of action will be decided after member states have been consulted, the UN agency said.
Israel has been criticized by human rights groups and foreign officials over its suspected use of a number of weapons during its aerial, naval and ground assault on the Palestinian territory.
Phosphorus investigation
The Israeli army claimed that it has launched an internal investigation into the use of white phosphorus, a highly incendiary substance that can burn away flesh to the bone.
On Wednesday, Israel's Haaretz newspaper reported that the inquiry would focus on the alleged firing of about 20 phosphorus shells around the northern town of Beit Lahiya by Israeli paratroopers.
Amnesty International, a London-based human rights group, has said that its use in Gaza's densely populated urban neighborhoods was a "war crime".
Amnesty International and Human Rights Watch, along with the United Nations relief agency in Gaza, have said there is widespread evidence of Israel's use of the controversial chemical munitions during the Gaza war.
Israel has previously refused to confirm that white phosphorus was used in the territory, but said that "all weapons were legal under international law."
Haaretz reported that the Israeli military fired a total of 200 white phosphorus shells during the three-week Gaza offensive.
'Rebuilding tunnels'
There have also been accusations that the Israeli military used Dense Inert Metal Explosive (Dime) weapons in urban areas causing horrific abdominal and leg injuries.
When detonated, a Dime device expels a blade of charged tungsten dust that burns and destroys everything within a four-meter radius.
One of Israel's stated aims of their offensive was to stop weapons being smuggled into the Gaza Strip.
PHOTO CAPTION
Palestinians stand amongst the rubble of a destroyed house in Jabalya in the northern Gaza Strip January 20, 2009.
Al-Jazeera