Turkish President Recep Tayyip Erdogan gestures during a joint press conference. AFP
At least five UNIFIL peacekeepers have been wounded in Israel attacks in recent days.
Erdogan said the UN was also to blame for failing to sanction Israel over its wars on Gaza and Lebanon.
"The image of the UN which cannot protect its own personnel is shameful and worrying," Erdogan said in a televised address.
"Frankly, we ask ourselves what the (UN) Security Council is waiting for to stop Israel.
"Can you believe it? The Israeli tanks penetrate into the UNIFIL zone, attack peacekeeping soldiers, even wounding some of them, but the UN Security Council decides to just watch all this criminality from its stands -- that's what we call powerlessness."
The UN condemned the attacks with Secretary-General Antonio Guterres saying they "may constitute a war crime".
He said that Israeli soldiers had "deliberately breached" a UNIFIL compound.
Israeli Prime Minister Benjamin Netanyahu on Sunday called on Guterres to move peacekeepers out of "harm's way."
UNIFIL, a mission of about 9,500 troops of various nationalities created following Israel's 1978 invasion of Lebanon, has refused to leave its positions.
It has accused the Israeli army of "deliberately" firing on its positions.
* This story was edited by Ahram Online.
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