A U.S. delegation led by Jared Kushner had a “productive” meeting with the Palestinian Authority on how to begin Middle East peace talks, the State Department said Friday, although some Palestinian officials expressed frustration that the Trump administration still has not committed to a two-state solution.

Both sides agreed to continue with the U.S.-led conversations as the best way to reach a peace deal, the State Department statement said. Palestinian President Mahmoud Abbas also struck a positive note in public comments a day earlier after meeting in Ramallah with Kushner, who is President Trump’s son-in-law and adviser, as well as Middle East envoy Jason Greenblatt and deputy national security adviser Dina Powell.

“We know that this delegation is working for peace, and we are working with it to achieve what President Trump has called a peace deal,” Abbas said at the beginning of the meeting, according to the Palestinian Authority news site Wafa. “We know that things are difficult and complicated, but there is nothing impossible with good efforts.”

The U.S. team is attempting to find a way to kick-start the Israeli-Palestinian peace process in hopes of reaching what Trump has called the “ultimate deal.” The Americans met with Abbas and Israeli Prime Minister Benjamin Netanyahu on Thursday, as well as with officials from Egypt, Saudi Arabia, the United Arab Emirates, Jordan and Qatar during the trip.

But the U.S. delegation refrained from committing to a two-state solution — the primary focus of peace efforts for decades. That has rankled Palestinian officials, who say that negotiations without any set parameters would benefit only the Israeli side. 

For weeks Palestinian officials have called on the United States to back a two-state solution and ask Israel to stop building settlements in the occupied West Bank, which most of the international community considers illegal and an obstacle to the creation of any future Palestinian state.

Most notably in a meeting with left-wing Israeli lawmakers last week, Abbas noted that he had met Trump’s envoys “about 20 times” but that they had failed to convey a commitment to a two-state solution to Netanyahu, according to leaked comments.

“We have clearly emphasized to the Americans the importance of having a public statement that has a commitment to the two-state solution,” said Ashraf Khatib, a spokesman for the Negotiations Affairs Department of the Palestine Liberation Organization. “There hasn’t been any.”

A small group of demonstrators gathered in Ramallah as the meeting took place Thursday, protesting a delegation that is widely seen as biased toward Israel.

“We have told the Americans that we are committed to the American effort,” Khatib said. “We’ve also told the Americans that we want clarity on their approach.”

U.S. officials have said that they have not ruled out a two-state solution but that it is up to the two sides, not them, to agree on a way forward.

Trump is “very committed to achieving a solution here that will be able to bring prosperity and peace to all people in the area,” Kushner said ahead of his meeting with Netanyahu.

Analysts say a corruption scandal engulfing the Israeli leader has left him increasingly beholden to fringe elements within his right-wing coalition, possibly making him an inflexible negotiating partner. The 82-year-old Abbas is also fighting for his political survival as he reaches the end of his tenure and is keen to carve out a legacy.

“Without a vision, it will be negotiations for negotiations’ sake,” Khatib said.