The United States reiterated on Tuesday that all Quartet demands must remain in place for dealing with any Palestinian national unity government that might be formed, amid reports the sides had reached some level of understanding. The Quartet of the US, EU, UN and Russia have demanded that Hamas renounce violence, recognize Israel and respect past agreements, moves that are anathema to the Islamist group. "We certainly favor an effective Palestinian government, and we are certainly supportive of a reconciliation process," State Department spokesman P. J. Crowley said of national unity talks between Fatah and Hamas being brokered by Egypt. "That said, we have particular terms, you know, laid out by the Quartet. You know, Palestinian unity must be guided, you know, in support of a government committed to nonviolence, recognition of Israel and acceptance of previous agreements and obligations." The US also said its commitment to the Palestinians "remains strong," as did its objections to Israeli settlement activity, following the publication of a Fatah memo saying hope in President Barack Obama had been lost. "All hopes placed in the new US administration and President Obama have evaporated," the document said. Obama "couldn't withstand the pressure of the Zionist lobby, which led to a retreat from his previous positions on halting settlement construction and defining an agenda for the negotiations and peace." "Our commitment to the Palestinian people remains strong," a State Department official responded, adding that American opposition to settlements remained in place: "We continue to emphasize that America does not accept the legitimacy of continued Israeli settlements." The Fatah memo accused the US of failing to set a clear agenda for a new round of Israeli-Palestinian peace talks. The State Department official stressed, though, that "our priority remains the resumption of negotiations in an atmosphere conducive to success," and furthermore that "it is past time to talk about starting negotiations - it is time to move forward." However, along with the circulation of the memo, a copy of which was obtained by The Associated Press, Fatah chairman and Palestinian Authority President Mahmoud Abbas declared that he wouldn't resume peace talks with Israel before there was a total freeze on settlement activity, including in Jerusalem. Israel had no formal response to the Fatah memo, or to Abbas's comments on not resuming negotiations without a freeze. But one government official said there was nothing new in the Palestinians blaming the "Zionist lobby" in Washington for their problems. Regarding the PA demand for a settlement freeze, the official said this, too, was not new. The official added that Prime Minister Binyamin Netanyahu had made it clear he would not accept any limitations on Israel's sovereignty in Jerusalem and would only - if conditions were ripe - agree to a temporary moratorium on new housing starts in the West Bank, but not a halt to the 3,000 units in various stage of construction or the approved planning process. The Palestinians initially greeted Obama's election with enthusiasm, welcoming his outreach to the Muslim world and hoping he would depart from what they viewed as the pro-Israel bias of his predecessor, George W. Bush. Obama raised Palestinian hopes further with his repeated calls for Israel to halt all Jewish construction in the West Bank and east Jerusalem. But in recent weeks, the US appears to have softened its stance on settlements. Washington says it has not abandoned the objective of halting settlement construction, but US officials have indicated they do not see this as a condition for resuming talks. The administration has also begun speaking of Israel "refraining" from building in settlements where it once stressed a total freeze. The State Department official communicated to The Jerusalem Post American displeasure with settlements, calling them illegitimate, but did not repeat calls for a freeze. The Palestinian memo, dated October 12, was issued by Fatah's Office of Mobilization and Organization. The office is headed by the party's No. 2, Muhammad Ghneim. It was not immediately clear whether the document reflected Abbas's views or whether it had been leaked to pressure Obama to bear down harder on Israel. Abbas's aides had no comment, and Ghneim could not immediately be reached for comment. The document echoes sentiments expressed by other Fatah officials. On Sunday, former Fatah strongman Muhammad Dahlan said the party "feels very disappointed and worried by the US administration retreat." Defense Minister Ehud Barak, meanwhile, said in Prague on Tuesday that the Palestinian leadership needed to "have the courage" to assist as soon as possible in moving the diplomatic process forward. He said that US Middle East envoy George Mitchell, who left the region on Sunday after five days of talks without a breakthrough, would return in a matter of weeks to "start the diplomatic process between us and the Palestinians." Netanyahu said earlier this week that US Secretary of State Hillary Clinton was also expected back in the region by the end of the month, although this has not yet been confirmed by Washington. Clinton is expected to give Obama a status report on the situation by "mid-October." Crowley only said in response that Clinton's travel plans "are still up in the air," but he noted that she was "committed to be in Morocco in early November" and that he expected that "there will be other stops added." AP contributed to this report.