Washington ? The White House has decided to provide direct funding to the Palestinian Authority for social service projects, Bush administration and congressional officials said Tuesday, marking an important shift in U.S. policy designed to bolster the new Palestinian prime minister and act as a counterweight to services provided by militant organizations like Hamas.

The initial funding is relatively small — $20 million — but its symbolic value is much more valuable. In the past, successive administrations and congressional restrictions have limited aid to Palestinians only through indirect sources, such as the United Nations or nongovernmental organizations. President Bush will seek a waiver from congressional restrictions, officials said.

The move represents the administration’s deepening commitment to the peace process Bush launched last month, as well as a major investment in Palestinian Prime Minister Mahmoud Abbas. But it comes amid new strains among the Palestinian leadership that threaten to derail the peace process. Abbas resigned Tuesday from the central committee of Fatah, the largest Palestinian political movement, in a dispute over relations with Israel, while a Palestinian group that last week agreed to a three-month cease-fire claimed responsibility for a bombing that killed an Israeli woman on Monday.

Abbas also threatened to resign Tuesday.

Administration officials stressed the urgency in the action, saying they wanted to get the funds to the Palestinian Authority as quickly as possible to shore up Abbas as he tries to establish credibility with the Palestinian people.

“It is very significant. This is the first time since the Palestinian Authority was established in 1994 that the United States has given direct assistance,” said Ed Abington, a Washington-based consultant to the Palestinians. “It puts them on a different footing in how we are dealing with them, opening the door wider in terms of dealing with them as a government.”