Donors have committed $7 billion to reconstructing Gaza, US President Donald Trump said at the Board of Peace's inaugural meeting in Washington, DC, on Thursday.
Members of the controversial organisation are gathering in the US capital to discuss the Trump administration's vision for post-war Gaza.
Qatar, Saudi Arabia, UAE, Kuwait and Bahrain are among the countries providing funds, Trump said in a speech opening the event.
The UN humanitarian agency will raise $ 2 billion, he said.
The UN has put the cost of rebuilding the devastated territory at around $70 billion.
The meeting, which comes a month after the signing of the organisation's charter at Davos, is expected to focus on financing the vast reconstruction effort of the destroyed enclave and assembling a multinational force to take over security from Palestinian armed groups.
Meanwhile, fears of a major US attack on Iran continue to climb amid a huge military build-up in the Persian Gulf.
The US military has deployed its largest air presence in the region since the 2003 invasion of Iraq, setting the stage for a large-scale attack should last-ditch negotiations over Iran's nuclear programme falter.
US news media reported on Wednesday that Trump could soon order an attack, despite both sides reporting "progress" in nuclear talks on Tuesday.