The U.N. Human Rights Council said it will hold an extraordinary meeting on Wednesday to discuss Israel's ongoing military offensive in Gaza.

Monday's announcement followed the deadliest day of fighting between Israel and Hamas in six years, with more than 150 Palestinians and 13 Israeli soldiers killed on Sunday.

World efforts to broker a ceasefire in war-torn Gaza gathered pace Monday as Israel pressed a blistering 14-day assault on the enclave, pushing the Palestinian death toll to 572.

As Washington and the United Nations demanded an "immediate ceasefire" in the battered Palestinian enclave, Israel announced that seven more of its soldiers had been killed during fighting in Gaza, raising the overall Israeli death toll to 27, all but two of them soldiers.

Arab Israelis clashed with police in the northern city of Nazareth on Monday, police said, at the end of a protest against Israel's deadly military strikes in the Gaza Strip.

The clashes came as Nazareth and cities in the West Bank observed a general strike to mourn the victims of the Gaza conflict between Israel and Hamas -- the bloodiest since 2009 -- that has cost more than 500 Palestinian lives in two weeks.

Kuwait called on U.N. Secretary General Ban Ki-moon on Monday to urge the international community to put an end to the Israeli "aggression" in Gaza which has claimed 508 lives.

The call came in a meeting between Foreign Minister Sheikh Sabah Khaled Al-Sabah and Ban who arrived in Kuwait on Monday in the second leg of a regional tour aimed at pushing for a ceasefire in Gaza.

U.S. Secretary of State John Kerry appeared to criticize Israel in candid remarks caught on an open microphone between television interviews Sunday.

Kerry was heard talking about Israeli soldiers killed in Gaza to a State Department official identified as Jonathan Finer just before appearing on the "Fox News Sunday" political talk show.

A French rally against the deadly Israeli offensive in Gaza once again descended into chaos Sunday as protesters looted shops and riot police lobbed tear gas and rubber bullets into the crowds.

The demonstration in the northern Paris suburb of Sarcelles is the third to have deteriorated in the space of eight days in a country that counts the largest Muslim population in western Europe and a huge Jewish community.

The U.N. Security Council late Sunday deplored the mounting death toll in Gaza and appealed for an immediate ceasefire at an emergency session held on the worst day of fighting.

Meeting for two hours of urgent talks in New York, the 15-member Council also called for respect of international humanitarian law, including the protection of civilians.

The number of Palestinians killed by Israeli fire in the latest round of Gaza violence rose to 476, medics said, after announcing the deaths of 38 people early Monday.

Emergency services spokesman for the Gaza Strip Ashraf al-Qudra said they had found the bodies of three children and a man in a demolished home east of Khan Yunis in southern Gaza.

United Nations Secretary-General Ban Ki-Moon urged Israel to "exercise maximum restraint" and spare the lives of civilians in its campaign in Gaza, where Sunday's Palestinian death toll passed 100.

He also condemned the "atrocious action" of Israel in Shejaiya, near Gaza city, where a blistering hour-long assault at dawn left 62 people dead and at least 250 people wounded.

President Barack Obama expressed concern over the loss of life in Gaza in a call to Israeli Prime Minister Benjamin Netanyahu Sunday, and said Secretary of State John Kerry will travel to Cairo to seek an end to the fighting.

Obama, who condemned attacks by Hamas on Israel, "also raised serious concern about the growing number of casualties, including increasing Palestinian civilian deaths in Gaza and the loss of Israeli soldiers," the White House said, adding that Kerry will travel "soon" to the Egyptian capital.