Israeli Prime Minister Benjamin Netanyahu said Kushner briefed participants at a security conference in Poland about the anticipated plan but would not go into details for fear of it leaking. Netanyahu told reporters that he looked forward to "seeing the plan once it is presented."
Netanyahu said he heard nothing new from Kushner besides a reference to a 2002 Saudi Peace Initiative, which offered full Arab recognition of Israel in return for a withdrawal from territories it captured in the 1967 Mideast war. Netanyahu said Kushner said the plan may have made sense at the time but was no longer relevant.
"It is not appropriate for today. The reality has changed," Netanyahu said.
He wouldn't comment on any concessions Israel would have to make under any U.S.-backed proposal.
A diplomat who watched Kushner's presentation quoted him as saying that Trump had given him the Israeli-Palestinian "file" to give the long-elusive goal of a peace agreement "a shot." Despite the long odds, he said he believed "privately, people are much more flexible" than their public positions, the diplomat said, speaking on condition of anonymity according to protocol.
The Palestinians have pre-emptively rejected the plan, accusing the Trump White House of being unfairly biased in favor of Israel. The apparent rejection of the Saudi peace plan is likely to deepen their belief that the plan will fall far short of their longstanding goal of establishing an independent Palestinian state in the Israeli-occupied West Bank, east Jerusalem and the Gaza Strip.
"There will be no peace and stability in the Middle East without a peaceful solution that leads to a Palestinian state, with Jerusalem as a capital," said Nabil Abu Rdeneh, a spokesman for Palestinian President Mahmoud Abbas.
The Palestinians skipped Thursday's conference and asked Arab countries to boycott or downgrade their representation. Some 60 countries took part in the gathering, including five Arab foreign ministers that made a rare public appearance alongside Netanyahu.
Kushner has been working on an Israeli-Palestinian peace plan for close to two years but has yet to release any details, and the release of his plan has been repeatedly delayed.
U.S. officials had said Kushner would make some comments in Warsaw about the conflict. But Netanyahu said ahead of time he didn't expect any discussion of the peace plan, with the focus of the conference on participants' shared concern over Iran and its growing influence in the region.
The diplomat quoted Netanyahu joking at some point to Kushner that "having this file" is a "tough one."
"But, if you are crazy enough, and I think you might just be, you can come up with new ideas," he quoted Netanyahu as saying.
Netanyahu also urged all interested parties, particularly the Palestinians, to wait for the plan to come out before reacting to it or rejecting it.
U.S. officials have signaled the plan will be heavily focused on Palestinian economic development. They also have refused to endorse the concept of a Palestinian state — a goal that has enjoyed wide international backing for the past two decades.
The U.S. recognition of contested Jerusalem as Israel's capital, along with the cancellation of hundreds of millions of dollars in American aid to the Palestinians, have prompted the Palestinians to cut off ties with the White House and pre-emptively reject the peace plan.
While facing Palestinian resistance, the plan could also run into Israeli opposition.
Netanyahu's governing coalition is comprised of religious and nationalist hardliners who oppose serious concessions to the Palestinians. With Netanyahu seeking re-election and pledging to form a similar coalition if he wins, it is unlikely that he would make any concessions, particularly before the April 9 vote.
Kushner, according to the diplomat, said the history of the Middle East had shown that "pessimists" about Israeli-Palestinian peace were "usually right." But he stressed that "it's the optimists that bring the change."
With the Palestinians sidelined, Netanyahu has tried to use the Warsaw conference to get closer to other Arab nations aligned with it against Iran.
Netanyahu has long boasted of clandestinely developing good relations with several Arab states, despite a lack of official ties. Bringing such contacts out into the open would mark a major diplomatic coup and put a seal of approval on his goal of improving Israel's standing in the world, and particularly with Arabs.
On Wednesday, Netanyahu met with Oman's foreign minister, Yusuf bin Alawi, and they issued a joint video statement. At Thursday's opening session he was seated next to the foreign minister of Yemen, Khaled al-Yamani, as representatives of Saudi Arabia, Kuwait, Qatar and others looked on.
Asked on the sidelines of the conference if Netanyahu could expect an invitation to his country, Bahraini Foreign Minister Khalid Al Khalifa: "I will leave matters to when it happens."
Briefing reporters later, Netanyahu declined to say whether he had met any other Arab leaders or what was discussed. But he did say the atmosphere at Thursday's gathering was "unfathomable" as far as the like-mindedness of the participants involved. He said when he spoke, the Arabs in the room listened intently, with some expressing very similar sentiments regarding the threat posed by Iran.
"Something amazing is happening here," he said. "There is a real change here ... we spoke about Iran, Iran, Iran."
Even as Gulf Arab states have dropped some of their traditional antipathy toward Israel, it remains unlikely they will fully normalize relations with Israel without some progress on the Palestinian front.
"I never said we'd reach a peace agreement with the Arab countries before we solve the Palestinian issue. But I have said that the policy I am leading will move toward normalization," Netanyahu said. "We can wait for the Palestinians from here till tomorrow, but I don't condition that on normalization with the Arab world."
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