Employees in the Tel Aviv embassy had a toast Friday to mark the last day for those who will return to work at the new location on Monday, a senior administration official said. Between 50 and 60 officials will be working at the embassy on Monday, including the consular officials, the official said.

In moving the embassy from Tel Aviv to Jerusalem, Mr. Trump reversed decades of America’s approach to the Holy City, one of the world’s most contested pieces of land. Congress passed a law in the 1990s requiring that the embassy be moved to Jerusalem, and other presidents had promised to do so, only to exercise a waiver in the law permitting them to hold off, for fear that it would set off a backlash and complicate peace negotiations.

Not only did Mr. Trump break from that by declaring Jerusalem to be Israel’s capital, but he has also abandoned America’s commitment to a two-state solution to the conflict that would involve the creation of a Palestinian state alongside Israel, a position that had been a bedrock of American policy for years. Mr. Trump has said he would be fine with a one-state solution if the two sides agreed, a position that has emboldened Israeli opponents of a Palestinian nation who have declared the death of the two-state solution.

Mr. Trump has promised to broker a peace agreement between Israel and the Palestinians, assigning the task to top advisers led by Jared Kushner, his son-in-law. But even though White House officials have said their plan is nearly complete, they have yet to release it, and neither side in the region appears prepared to compromise. The Palestinians, citing the embassy move, have cut off high-level contacts with the Trump administration, saying it cannot be a neutral mediator.

The embassy is partly in predominantly Jewish West Jerusalem and partly in a gray area between the west and predominantly Arab eastern section of the city. Palestinians have long hoped that East Jerusalem will be the capital of a future Palestinian state. Home to the third-holiest mosque in Islam as well as the holiest site in Judaism, the city poses highly sensitive issues for Muslims and Jews. The city is also sacred to Christians.

The State Department has not taken a clear position on the contested land in the embassy compound, but recognizes that Israel and Jordan had informally divided it and that it has been in continuous Israeli use since 1949.

Scheduled to attend the official opening are some members of Congress and a delegation led by John J. Sullivan, the deputy secretary of state; Steven Mnuchin, the Treasury secretary; and some of the president’s advisers, including his daughter, Ivanka Trump, and Mr. Kushner.