Bush is facing growing pressure at home to begin pulling troops out of Iraq. At the same time, U.S. officials have renewed requests for help from Middle East countries in stabilizing Iraq.
The regional meeting would be led by U.S. Secretary of State Condoleezza Rice. Bush said it would review progress on building Palestinian institutions.
"I will provide diplomatic support for the parties in their bilateral discussions and negotiations so that we can move forward on a successful path to a Palestinian state," Bush said.
Some $190 million in aid has been pledged for Abbas's government for the current fiscal year ending Sept. 30.
U.S. Assistant Secretary of State for Near Eastern Affairs, David Welch, said about $145 million was for humanitarian aid for the Palestinians channeled via the United Nations. A further $50 million is for democracy issues, building Palestinian institutions and private-sector development.
Separately, the Bush administration plans to put about $86 million into reforming Abbas's security forces of which Congress has already given the go-ahead for $59 million.
Rice had been scheduled to visit Israel and the Palestinian territories this week. The trip was postponed and instead Rice and Defense Secretary Robert Gates will visit unspecified Middle East countries late this month or early in August.
Middle East expert Shibley Telhami said the Bush administration's strategy of isolating Hamas could not work.
"I don't see how anything serious on the diplomatic front can be accomplished so long as the strategy to isolate Hamas continues," said Telhami of the University of Maryland.
Bush's ally, former British Prime Minister Tony Blair, this week assumes the role of envoy for the Quartet of Middle East mediators, which includes the United States, the European Union, Russia and the United Nations.
The Quartet, which will convene in Lisbon on Thursday, is expected to endorse Bush's plan for a regional meeting.
