At a black-tie dinner on the eve of his inauguration, Donald Trump expressed supreme confidence that his 36-year-old son-in-law, Jared Kushner, a political and diplomatic neophyte, would succeed in brokering what he has called the “ultimate deal”: a lasting peace between Israel and Palestine. “If you can’t produce peace in the Middle East, nobody can. All my life I‘ve been hearing that’s the toughest deal to make, but I have a feeling Jared is going to do a great job,” Trump declared. And yet, as he closes in on one of his many bold campaign promises, the president is about to throw a wrench into Kushner’s ambitious peace effort.

Trump is expected to announce on Wednesday that the United States recognizes Jerusalem as the capital of Israel and that it will eventually relocate its embassy to the city—a move widely expected to incite violence in the West Bank and undercut Kushner’s plan, which he has been working on for months. On Tuesday, the White House sought to minimize Trump’s imminent declaration, arguing that it was more about logistics than politics. “While President Trump recognizes that the status of Jerusalem is a highly sensitive issue, he does not think it will be resolved by ignoring the simple truth that Jerusalem is home to Israel’s legislature, its supreme court, and the prime minister, and as such is the capital of Israel,” one Trump administration official told Politico. “Delaying the recognition of Jerusalem as the capital of Israel has done nothing to achieve peace for more than two decades.”

Israeli Prime Minister Benjamin Netanyahu applauded the announcement, but Palestine—which seeks East Jerusalem as the future capital of an independent state—swiftly denounced the plan, intimating that it undermined the push for a two-state solution. “There is no way that there can be talks with the Americans. The peace process is finished. They have already pre-empted the outcome,” Palestinian official Hanan Ashrawi said. “They cannot take us for granted.”

A number of foreign and religious leaders have joined in the outcry. Deputy Prime Minister Bekir Bozdag of Turkey characterized the move as an act of “shortsightedness” that “is plunging the region and the world into a fire with no end in sight.” Egyptian President Abdel Fattah el-Sisi similarly warned that it “would undermine the chances of peace in the Middle East.” And Pope Francis said he was “profoundly concerned” about the decision and urged respect for the “status quo of the city.”

As the president announces the decision in a speech Wednesday, the spotlight will inevitably swing to Kushner, whose negotiating team has been described as hopelessly inexperienced. “There’s not a Middle East macher in this group,” Democratic donor Haim Saban told Kushner during an interview at his annual Saban Forum in Washington on Sunday. “With all due respect, it’s a bunch of Orthodox Jews who have no idea about anything.” Kushner pushed back, arguing that a peace deal is “achievable” and that his team has deliberately kept its strategy and timeline under wraps. “There’s no better real-estate lawyer than Jason Greenblatt, who’s been working on it,” he said, referring to the Trump administration attorney who now serves as special envoy to Israel. “There are a lot of real-estate issues to it.”

Despite international alarm, the White House reportedly believes that Trump’s announcement will not impact Kushner’s work—officials intimated to Axios that they see the move as increasing the president’s credibility with other world leaders, casting him “as someone who stands by his word, isn’t intimidated by threats, and doesn’t cave to international pressure.” (As a candidate, Trump repeatedly promised to move the U.S. embassy in Israel from Tel Aviv to Jerusalem.) Meanwhile, Kushner and his team are planning to “put their heads down for a while,” re-emerging to continue their efforts once the uproar has died down.