"We think that there's momentum for some additional parties to join and to normalize relations with Israel," said National Security Adviser Robert O'Brien.
"The Palestinian leadership rejects and denounces the UAE, Israeli and U.S. trilateral, surprising announcement," a spokesperson for Palestinian President Mahmoud Abbas said.
Many in the international community are deeply alarmed by the Trump/Kushner plan.
Trump is expected to unveil his peace plan alongside Israeli Prime Minister Benjamin Netanyahu in Washington, D.C.
"A Palestinian state must be established with security, borders and a capital before talking about any kind of confederation since it is needed to be able to achieve such a thing," said Ziad Abu Zayyad, an international spokesman for the Fatah party.
The leader has been president of the Palestinian National Authority since 2005.
Abbas had been condemned for saying the persecution of Jews was due to their conduct and not their religion.
The Palestinian Authority president gave a conspiracy theory-laden speech.
"We are ready to begin negotiations immediately in order to achieve the freedom and independence of our people."
In just two days, dozens of Saudi officials were arrested and two princes killed, and talks of war with Iran ignited.
Fatah says it is ready for reconciliation with its Palestinian rival.
Trump and Jared Kushner's efforts to get Israel and the Palestinians to the table have stalled.
Netanyahu criticized Abbas after a public square in Jenin was named after Palestinian militant Khaled Nazzal.
Just the fact that Trump committed his administration to an Israeli-Palestinian peace process sends a message of defiance to the Israeli leadership.
Abbas said he agreed with Trump's call for Israel to refrain from settlement building in the occupied West Bank and East Jerusalem.
Muhammadu Buhari says Nigeria will back Palestinians until "their desired objectives" are achieved.
Prime Minister Rami Hamdallah is ready to step down after talks between rival factions.
The political conflict between Hamas and Fatah appears intractable, writes Jonathan Schanzer.
The pair met at the climate change summit that began on Monday in Paris.
Diplomatic efforts to try to end a surge in violence in Israel resumed in Jordan.
Two decades after the Israeli prime minister's death, the olive branch of peace between Israelis and Palestinians has been replaced by a dagger.