President Donald Trump plans to recognise Jerusalem as the capital of Israel and move the American Embassy there, upending nearly seven decades of US foreign policy and potentially destroying his efforts to broker peace between Israel and the Palestinians.

Trump’s decision, a high-risk foray into the thicket of the Middle East, was driven not by diplomatic calculations but by a campaign promise. He appealed to evangelicals and ardently pro-Israel American Jews in 2016 by vowing to move the embassy, and advisers said on Tuesday he was determined to make good on his word.

But the president, faced with a deadline of this past Monday to make that decision, still plans to sign a national security waiver to keep the embassy in Tel Aviv for an additional six months, even as he set in motion a plan to move it to Jerusalem. Officials said the process would take several years.

More significantly, Trump is to announce his formal recognition of Jerusalem as the Israeli capital in a formal speech at the White House on Wednesday, when he will become the first US president to take that step since the founding of Israel in 1948.

Trump spent Tuesday morning explaining the policy change in telephone calls with Prime Minister Benjamin Netanyahu of Israel; Mahmoud Abbas, the Palestinian Authority president; and Arab leaders who warned him that it would disrupt the peace process, perhaps fatally, and could unleash a new wave of violence across the region.

“Moving the US embassy is a dangerous step that provokes the feelings of Muslims around the world,” King Salman of Saudi Arabia told Trump in their call, according to Saudi state television.

Late Tuesday, Palestinian national and Islamic groups issued a joint statement calling for three days of “popular anger” to protest Trump’s move, beginning on Wednesday throughout the Palestinian territories and in demonstrations at US embassies and consulates around the world.

Fearing attacks, the US consulate in Jerusalem barred employees and family members from going to the Old City or the West Bank, while the State Department urged embassies around the world to tighten their security.

Jerusalem is one of the world’s most fiercely contested swaths of real estate, with both sides disputing each other’s claims. West Jerusalem is the seat of Israel’s government, but the Palestinians view East Jerusalem as the capital of a future Palestinian state, and most of the world considers it occupied territory. Jerusalem’s Old City has the third-holiest mosque in Islam and the holiest site in Judaism, making the city’s status a sensitive issue for Muslims and Jews worldwide.

Trump’s decision drew applause from some in Israel and the United States, even if Netanyahu and the Israeli government were studiously silent in advance of the president’s speech.

“The US recognising Jerusalem as Israel’s capital is a positive and important step particularly amid Palestinian efforts to undermine the historic ties between the Jewish nation and the City of David,” said Amos Yadlin, executive director of Tel Aviv University’s Institute for National Security Studies.

Morton Klein, president of the Zionist Organization of America, said, “It is high time to move the embassy to Jerusalem.” He added, “not moving it to Jerusalem for 22 years has not brought us closer to peace.”

White House officials said Trump remained committed to what he has called the “ultimate deal” between Israel and the Palestinians. The decision, they said, was “recognition of current and historic reality.” They said it could hasten rather than impede peace negotiations by removing a source of ambiguity from the US position.

Trump, officials said, would make clear that the United States is not taking a position on whether, or how, Jerusalem is divided between Israel and the Palestinians. He will also not take a position on a disputed area of the Old City, known as the Temple Mount to Jews and the Haram al-Sharif to Muslims, which has been a flash point for tensions.

But even with those caveats, Trump’s decision seems likely to disrupt, if not dissolve, the peace effort. Administration officials said they expected the Palestinians to walk away from the process, at least for now. The White House is girding itself for an eruption of violence, coordinating plans with several agencies to protect US citizens abroad.

“You can finesse this all you want, but Jerusalem doesn’t allow for any finesse,” said Martin S. Indyk, a former American ambassador to Israel. “They can try to limit the damage all they want, but they won’t be able to, because Jerusalem is such a hot-button issue.”

Mark Landler reported from Washington and David M. Halbfinger from Jerusalem. Julie Hirschfeld Davis contributed reporting from Washington.