Muslim nations have angrily condemned Israel for its air attacks on Gaza.
Anti-Israel demonstrations were held in many countries following a series of protests at the weekend. Efforts to hold talks between Syria and Israel have been suspended.
Thousands of Iranians protested in Tehran, and Iran's supreme leader Ayatollah Ali Khamenei urged Muslim states to punish Israel.
In Turkey, there were demonstrations in about a dozen cities, and there were protests in Egypt, Syria and Jordan.
Saudi Arabia has sent two hospital aircraft with medical personnel to Gaza.
Indonesia, the world's most populous Muslim nation, joined Pakistan, Afghanistan, Malaysia and others in condemning Israel.
Air attacks on Hamas centres in Gaza began on Saturday after Hamas ended a ceasefire with Israel on 19 December.