Teams from some 75 nations are in Sharm el-Sheikh, among them US Secretary of State Hillary Clinton.

In his opening speech, Egyptian President Hosni Mubarak said the "priority is to reach a truce between Israel and Palestinians".

The Palestinian Authority is seeking $2.8bn (£2bn) in foreign aid.

Thousands of homes and businesses were destroyed in the three-week offensive.

However, all but essential supplies are still subject to Israeli blockades at the crossing points into Gaza.

And donors stress that aid should not be channelled through Hamas, which both the US and the EU regard as a terrorist organisation.

Some 1,300 Palestinians, of whom 412 were children, were killed during fighting in December and January.

Israel and Hamas declared unilateral truces on 17 January. Neither are attending the conference.

Clinton's warning

Palestinian Authority President Mahmoud Abbas has asked for $2.8bn (£2bn) of aid from donors during the one-day conference at Egypt's premier Red Sea resort.

"We expect rapid international aid from all parties to completely rebuild Gaza," Mr Abbas told

reporters ahead of the conference.

He also stressed that all aid to Gaza should be channelled through his Palestinian Authority, not Hamas, which won elections to the Palestinian parliament in 2006 and consolidated its control by force a year later.

Hillary Clinton, who is making her first visit to the Middle East as America's top diplomat, is reportedly carrying a cheque for $900m for Gaza.

But she has already warned that the aid would depend on Palestinians' meeting the conditions of the "Quartet" of Middle East mediators - the EU, UN, US and Russia.

"I will be announcing a commitment to a significant aid package. But it will only be spent if we determine that our goals can be furthered rather than undermined or subverted," she said on Saturday.

After the conference, Mrs Clinton will go to Israel and the Palestinian territories to meet leaders from both sides.

Saudi Arabia, another major donor, has already promised $1bn (£703m) to Gaza, and is expected to reaffirm its commitment in Sharm el-Sheikh.

'Open crossings'

The main obstacle to reconstruction of Gaza are the crossings which remain largely closed to all

but essential supplies, says the BBC's Christian Fraser in Sharm el-Sheikh.

John Ging, head of the UN relief and works agency (Unrwa) in Gaza, said they were currently not even able to get donated food and medicine through.

"Unless the crossings are open we cannot expect any improvement in the situation here," he said.

"It's more urgent today than it has ever been before to find a solution to get these crossing points open, to get these materials in."

Israel said it fully supported the conference and the idea of strengthening support for the people of Gaza through humanitarian and reconstruction aid.

"But we must be clear," spokesman Mark Regev said. "Like the international community, Israel does not want to see support to Hamas. We want to see support for the people of Gaza."

Although Israel and the Middle East Quartet refuse to speak to Hamas, UN agencies working in Gaza do co-ordinate with the Hamas government.

UN relief agency Unrwa says it has contacts with Hamas "even at ministerial level", but strictly on technical issues related to the delivery of its humanitarian services in line with wider UN policy.