WASHINGTON — Secretary of State Rex W. Tillerson said Tuesday that it is unlikely that the American Embassy will be moved to Jerusalem before 2020.

“It’s not going to be anything that happens right away,” Mr. Tillerson said, adding, “Probably no earlier than three years out, and that’s pretty ambitious.”

President Trump formally recognized Jerusalem last week as the Israeli capital, but he nevertheless signed a national security waiver, which will allow him to delay the movement of the embassy to Jerusalem from Tel Aviv for an additional six months. Administration officials have said there are functional and logistical reasons the United States cannot open a new embassy any time in the near future.

There are also policy advantages to delaying the move, particularly if the administration wants to keep the peace process alive. The United States can spare itself a series of delicate decisions — like where in Jerusalem to build the embassy — that would begin to define the geography of Mr. Trump’s deliberately general statement about the city’s status.