"If we get something, if they can agree on some things as an input to the negotiations, that would be fine," Hadley said. "But I think it is really no longer on the critical path to a successful conference."
Saeb Erekat, the Palestinian negotiator, said the Annapolis meeting was a time to make decisions on permanent status negotiations.
"We don't need to reinvent the wheel," he told Al Jazeera. "We know it is going to be a two state solution."
But Israeli, Palestinian and US negotiators were still trying to put a framework together for the talks, something the US had hoped would be completed by now.
Sean McCormack, a state department spokesman, said: "We're confident there will be a document and we'll get to Annapolis in good shape on that."
But bargaining is expected to continue behind the scenes when the Annapolis meeting gets under way on Tuesday.
Michael Tarazi, a former adviser to the PLO, told Al Jazeera: "It would be a mistake to think that anything meaningful is going to come out of these talks.
"This is a conference where people are going to talk about beginning to talk.
"The real important thing is not what happens at Annapolis, but rather what happens the day after - is there really going to be momentum to address the really thorny issues?"
Washington has pushed for a broad Arab presence at the talks and on Sunday, Syrian media reported that Faysal Mekdad, the deputy foreign minister, would attend.
The presence of Syria, which borders Israel but has no diplomatic relations with the state, is at least a partial victory.
Tzipi Livni, the Israeli foreign minister, told reporters en route to Washington: "There isn't a single Palestinian who can reach an agreement without Arab support. That's one of the lessons we learned seven years ago."
But she added, "it is not the role of the Arab world to define the terms of the negotiations or take part in them".
On Sunday evening, Erekat and Ahmed Qureia, another Palestinian negotiator, met Livni for unscheduled talks.
Asked if they were optimistic about the prospect for reaching a consensus on a joint declaration, Qureia replied: "You don't meet if you're not optimistic."
David Welch, the US assistant secretary of state for near eastern affairs, also met Palestinian negotiators on Sunday in an attempt to reach a breakthrough ahead of Tuesday's gathering, a member of the Palestinian delegation said.