The Palestinian prime minister on Monday urged international donor nations to honor their pledges to send billions of dollars to help rebuild the Gaza Strip after the devastating 50-day Israeli assault on the enclave, warning that similar promises in the past have come up empty.

The call from Rami Hamdallah came during a meeting with visiting U.N. Secretary-General Ban Ki-moon, who is in the region to shore up international efforts to rebuild Gaza.

In 50 days of fighting, more than 2,100 Palestinians were killed, most of them civilians, according to the United Nations. An additional 11,000 people were wounded and some 100,000 people were left homeless. Seventy-two people on the Israeli side were killed, including 66 soldiers.

Israel has accused Hamas of using Gaza civilians as human shields and claims the number of Hamas fighters killed was much higher than the U.N. figures.

At a news conference with Ban in Jerusalem, Israeli Prime Minister Benjamin Netanyahu accused the U.N. of being complicit in rocket fire.

"When rockets were discovered in U.N. schools, some U.N. officials handed them back to Hamas, that very same Hamas that was rocketing that very same time Israeli cities and Israeli civilians," Netanyahu said.

Ban did not address Netanyahu's accusations, but Pierre Krahenbuhl, the commissioner of the U.N. agency for Palestinian refugees, which runs the U.N. schools in Gaza, has "categorically" rejected the Israeli charges.

Instead, Ban thanked Israel for supporting the Gaza reconstruction efforts, and in addition, called for an easing of a longstanding blockade of the coastal strip.

Israel and Egypt imposed the blockade after the Hamas takeover, largely restricting the movement of people and goods in and out of Gaza and stifling the local economy.

"Large-scale reconstruction must start without delay, but this is not enough to break the cycle," Ban said. "If conditions in Gaza simply revert to where they were before this escalation, the clock will be reset for more instability, underdevelopment and conflict."

"Economic revival, which requires the predictable exit and entry of goods and people, can change the dynamics on the ground and ultimately enhances stability in Gaza, which in turn will improve Israel's security," Ban said.

At a conference in Cairo, donor nations on Sunday promised to provide $5.4 billion to the Palestinians, half of which is earmarked for rebuilding the war-battered territory, a narrow sliver of land along the Mediterranean that is wedged between Israel and Egypt and has 1.8 million people.

The Western-backed Palestinian Authority, headed by President Mahmoud Abbas, will be in charge of managing the money, in coordination with Israel and the United Nations.

Hamas, the group that has run Gaza for the past seven years, has agreed to step aside to allow the Palestinian Authority to begin reconstruction operations, though Hamas has said it will not give up its weapons arsenal.

Hamdallah said it is critical that the donor nations keep their promises to provide the aid. He noted that after a previous attack in 2009, only a small fraction of pledged money was actually sent.

"Our plans are ready for the reconstruction, but it depends on the flow of the money," he said. "In 2009, most of the pledged money did not come. We hope that this time is different."

The summer offensive was the most devastating of three rounds of violence between Israel and Hamas over the past six years.

*This story was edited by Ahram Online.