Turkish President Recep Tayyip Erdogan. AP
"The UN cannot even protect its staff. What are you waiting for to act? The spirit of the United Nations is dead in Gaza," Erdogan told lawmakers from his AKP party.
Erdogan's comments came as the UN Security Council met to discuss a deadly Israeli attack on a displacement camp west of Rafah on Tuesday that killed 45 Palestinians.
The Turkish leader also hit out at fellow Muslim-majority countries for failing to take common action over the Israeli strike.
"I have some words to say to the Islamic world: what are you waiting for to take a common decision?" Erdogan, who leads a Muslim-majority country of 85 million people, told lawmakers from his AKP party.
"Israel is not just a threat to Gaza but to all of humanity," he said.
"No state is safe as long as Israel does not follow international law and does not feel bound by international law," Erdogan added, repeating an accusation that Israel is committing "genocide" in Gaza.
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