Both sides emphasized that many obstacles stand between them and a final deal on setting up a Palestinian state alongside Israel.
Talks will be complex, said Israel's chief negotiator, Tzipi Livni. She said she was heading to the Washington meetings, which are to begin later Monday, "cautiously, but also with hope."
Hanan Ashrawi, a Palestinian spokeswoman, said the upcoming talks are being held under more difficult conditions than previous negotiations. She cited the Palestinian political split, with Western-backed moderates and Islamic militants running rival governments, and the more hawkish positions of Israel's prime minister, Benjamin Netanyahu, compared to his predecessor.
"But I think there is a recognition of the urgency," she said. "If we don't move fast and decisively, things could fall apart."
The preliminary talks in Washington were made possible after Israel's Cabinet on Sunday agreed in principle to release 104 long-held Palestinian prisoners, convicted of offences including the killing or wounding of Israelis and the killing of suspected Palestinian collaborators.
The prisoners are to be released in four stages, with each release linked to progress in negotiations.
The resumption of direct Israeli-Palestinian contacts was a result of six months of shuttle diplomacy by U.S. Secretary of State John Kerry.