GENEVA

The International Federation of Red Cross and Red Crescent Societies (IFRC) and the International Committee of Red Cross (ICRC) said Saturday they are "alarmed" by Israel's Gaza evacuation order.

"We are deeply alarmed by the call for relocation in Gaza," the head of the IFRC, Jagan Chapagain, and Robert Mardini, director general of the ICRC, said in a joint statement on the escalation of hostilities in Israel and Gaza. "Our volunteers refuse to leave and abandon those who need them most. They must be protected so that they can protect others."

Underlining that nothing can justify the "horrific loss of civilian lives" in Israel last weekend, they said: " But such tragedy cannot in turn justify the limitless destruction of Gaza."

"The needs are staggering and will only continue to increase if the hostilities persist," they said.

They also urged all parties to exercise restraint, to abide by their obligations under international humanitarian law and to protect civilians.

The Israeli army ordered all residents of northern Gaza to evacuate their homes Friday and head south, despite warnings that it would lead to an international humanitarian disaster.

One week ago, Israeli forces launched a sustained and forceful military campaign against the Gaza Strip in response to a military offensive by the Palestinian group Hamas in Israeli territories.

The conflict began last Saturday when Hamas initiated Operation Al-Aqsa Flood against Israel -- a multi-pronged surprise attack including a barrage of rocket launches and infiltrations into Israel via land, sea and air.

Hamas said the operation was in retaliation for the storming of the Al-Aqsa Mosque in occupied East Jerusalem and Israeli settlers’ growing violence against Palestinians.

The Israeli military then launched Operation Swords of Iron against Hamas targets within the Gaza Strip.

Israel's response has extended into cutting water and electricity supplies to Gaza, further worsening the living conditions in an area that has endured a crippling siege since 2007, as well as ordering more than 1 million Gazans in the northern strip to evacuate to the southern strip within 24 hours.