A second cache of documents released by the Al Jazeera television channel quotes Palestinian President Mahmoud Abbas as saying it would be "illogical" to ask Israel to absorb 5 million refugees as part of a final peace deal.
The documents appears to contradict the Palestinians' public position that all refugees from the 1948-49 war and their descendants have the right to return to Israel.
The leaked files alleged that Mr. Abbas privately acknowledged the return of even 1 million refugees would mean "the end of Israel" and does not seem practical.
Palestinian negotiators are said in the documents to have requested that Israel allow the return of 10,000 refugees a year for 10 years - a total of 100,000.
At another point, Palestinian negotiators were said to have agreed that only a token number of refugees - just 10,000 - should return to Israel.
Israeli leaders say a mass resettlement is out of the question because it would undermine the state's Jewish majority.
A top aide to Abbas Monday accused the Persian Gulf state of Qatar, where Al Jazeera is based, of consciously seeking to damage Palestinian interests. He said the report released by the Doha-based Arab satellite channel relies on out-of-context quotes, insinuations and outright fabrications.
Yasser Abed Rabbo said Qatar's emir gave "a green light" for a political campaign against the West Bank Palestinian leadership. Qatar has close ties to Hamas, the Islamist group that controls the Gaza Strip. Hamas says the documents show that it is the true leader of Palestinians and has called the documents' revelations a betrayal.
The Qatari government bankrolled Al Jazeera when it launched in 1996 and is believed to still fund the station.
The new documents also reveal that in the course of peace talks in 2008 and 2009, then-Israeli Foreign Minister Tzipi Livni proposed moving several Arab villages now in Israel into a future Palestinian state as part of a land-swap deal for West Bank Jewish settlements.
Chief Palestinian negotiator Saeb Erekat said negotiations with Israel included discussion of some ideas that the Palestinians "could never agree to." He added that "no agreement will be signed without the approval of the Palestinian people."
In Ramallah late Monday, an angry crowd of about 250 Palestinians gathered outside the West Bank's main Al Jazeera office, with some smashing the station's logo and glass panels in the front door.
Confidential documents obtained by Al Jazeera allege that Palestinian negotiators secretly offered concessions, including an agreement to cede almost all of occupied East Jerusalem to Israel.
Abbas said Monday, during a visit to Cairo, that the proposal, which Al Jazeera reported to be from the Palestinian side, was actually an Israeli position.
The leaked transcript of a June 2008 meeting between Palestinian, U.S. and Israeli officials said chief Palestinian negotiator Ahmed Qurei proposed that Israel keep all but one of the major settlements it built in East Jerusalem after capturing that part of the city during the 1967 Mideast war.
The nearly 1,700 files cover an 11-year period from 1999 to 2010 and have been described by Al Jazeera as the largest leak of confidential documents related to the Israeli-Palestinian conflict. Al Jazeera has shared the documents with Britain's The Guardian newspaper, which says it has verified most of them.