A bumpy road is foreseen for the reconstruction of devastated Gaza even though international donors extended a generous helping hand at an Egypt-hosted conference on Monday.

"What's the meaning of rebuilding Gaza if Israel can easily destroy everything by missiles in minutes," a Chinese world news observer said.

"A sustainable ceasefire and opening crossings for the aid to get in are a must if they mean it," the observer said.

These two widely-recognized preconditions for reconstruction were also urged by participants at the Sharm El-Sheikh conference.

UN Secretary-General Ban Ki-moon warned that aid for Gaza's rebuilding would be impossible if border crossings between Gaza and Israel remained closed.

"The situation at the border crossings is intolerable," he said, adding that "aid workers do not have access. Essential commodities cannot get in" and therefore the "first and indispensable goal" is to open the crossings.

Israel tightened its Gaza blockade after it launched a massive offensive against the Palestinian coastal enclave, only allowing in limited humanitarian aid.

Ban also stressed that the reconstruction of Gaza needs a durable ceasefire. "When building a house, we begin with the foundation ... When it comes to rebuilding Gaza, this foundation must be a durable ceasefire," he said.

The Israeli leaders, meanwhile, have been trying to shift the international focus on Gaza's reconstruction to Iran.

Israeli Prime Minister-designate Benjamin Netanyahu has spoken of a Palestinian self-rule government but has never mentioned he would back a two-state solution to the Middle East conflict.

The hawkish Likud leader is a stanch supporter of the expansion of Jewish settlements in the occupied West Bank, a policy which Palestinians say could deny them a viable state.

In addition, how to push forward with reconstruction is a problem, with the Palestinian National Authority (PNA) being designated to lead the efforts while Hamas, which controls Gaza, being isolated.

The schism between Hamas and Fatah turned worse in mid-2007 after Hamas routed Fatah-dominated security forces loyal to Abbas to seize the Gaza Strip and PNA President Mahmoud Abbas sacked the Palestinian unity government led by Hamas and set up a Western-backed government in the occupied West Bank.

Though Egypt set in motion a dialogue among different Palestinian factions in February, the reconciliation efforts have borne little fruit so far.

The PNA in the West Bank and the Hamas-run government in Gaza have each insisted on leading the rebuilding effort, but Western countries, which consider Hamas a terror group, have said they can only work with Abbas.

US Secretary of State Hillary Clinton pledged at the conference that the United States will donate US$900 million for the Palestinians to shore up the PNA and help rebuild Gaza, but stressed that no funds will go to Hamas.

Abbas said last Saturday that international aid has to go through the PNA in coordination with international organizations.

The pledge of funding for rebuilding Gaza reached US$4.481 billion on Monday, almost twice that of the PNA's request of US$2.8 billion before the conference.

The humanitarian fund will likely be funneled through UN agencies and international aid groups.

Donors were to determine later how to implement the reconstruction money, but the conference said the fund would follow a reconstruction plan put together by Palestinian Prime Minister Salam Fayyad.

Israel's three-week attack against Gaza that ended on Jan. 18 left more than 1,300 Palestinians dead, 5,500 others wounded and more than 50,000 homeless, according to UN reports.