U.N. chief Ban Ki-moon demanded Tuesday that Israel and Hamas halt spiraling violence in Gaza as he pushed diplomatic efforts to end bloodshed that has killed more than 620 Palestinians.

Following top-level truce talks in Cairo, the U.N. secretary-general headed to Israel to deliver his message in person as the 15-day conflict showed no sign of easing.

Prime Minister Recep Tayyip Erdogan has sacrificed any possibility of Turkey playing a mediation role in Gaza in favor of seeking to impress voters ahead of presidential polls with the toughest ever anti-Israeli rhetoric from a Turkish leader.

Before the rise to power of Erdogan's Islamic-rooted Justice and Development Party (AKP) over a decade ago, NATO member Turkey was Israel's key ally in the Islamic world, a policy enthusiastically cheered by the United States.

Turkish Prime Minister Recep Tayyip Erdogan said he has stopped talking to U.S. President Barack Obama on the phone, amid growing strains between Ankara and Washington over Syria and the Gaza conflict.

Turkey, a fierce opponent of Syrian President Bashar Assad and an open supporter of armed rebel fighters, felt betrayed when the United States backed away from military action against Damascus in September.

French Prime Minister Manuel Valls has blamed extremist groups for violent pro-Palestinian protests that took place last week in and near Paris.

A demonstration in the gritty northern Paris suburb of Sarcelles degenerated into violence Sunday with Jewish shops being looted and police using tear gas and rubber bullets against the crowd.

The Israeli army on Tuesday confirmed that a soldier who Hamas militants claimed they had kidnapped is dead and his body remains unaccounted for.

The army named the soldier, whose body is still missing, as Oron Shaul, two days after Hamas said they had kidnapped an Israeli soldier of the same name.

The Israeli campaign against the Gaza Strip will play a major role in “reorganizing” the power of the resistance in Lebanon, the Palestinian territories, and the region, reported As Safir newspaper on Tuesday.

This was reflected in the telephone call between Hizbullah chief Sayyed Hassan Nasrallah and Hamas leader Khaled Meshaal on Monday, added the daily.

The United States on Monday condemned a weekend attack on an Egyptian border checkpoint which left 21 soldiers dead, and vowed to keep up support for Egypt's security.

The U.N. agency for Palestinian refugees said Monday the number of people seeking refuge at its sites in Gaza to escape a two-week-old Israeli offensive on the enclave has soared to more than 100,000.

"This is a watershed moment for UNRWA, now that the number of people seeking refuge with us is more than double the figure we saw in the 2009 Gaza conflict," climbing to above 100,000, the agency's spokesman Christopher Gunness said in a statement.

U.S. Secretary of State John Kerry arrived in Cairo on Monday to throw his weight behind efforts to secure a ceasefire in neighboring Gaza.

Kerry will meet U.N. Secretary-General Ban Ki-moon who is also in Cairo for talks with Egyptian officials aimed at ending the two-week conflict between Israel and Gaza militants.

Russia on Monday called for a ceasefire between Israel and Hamas and for the international community to urgently take concerted action to stop the suffering of civilians on both sides.

"The new dangerous cycle of violence has shown with absolute clarity the need for a ceasefire," the Russian foreign ministry said in a statement as the United States and the United Nations demanded an immediate ceasefire.