President Trump signed a waiver Thursday that delays his campaign promise to move the U.S. Embassy in Israel to Jerusalem, the White House said Thursday.

Trump's waiver suspends the move under the Jerusalem Embassy Act for six months. The law, passed in 1995, required the embassy to be moved to Jerusalem by the end of the 20th century, or else the State Department's building budget would be cut in half.

However, the law allowed the president to sign six-month waivers if it did not serve the national interest to move the embassy. Every president since the bill became law — Bill Clinton, George W. Bush, Barack Obama and now Trump — all signed waivers.

During the campaign, Trump promised to move the U.S. Embassy in Israel from Tel Aviv to Jerusalem. He maintained that promise up until the night before the election when he told a Times of Israel reporter, "You know I'm not a person who breaks promises."

White House press secretary Sean Spicer said in a statement that Trump still plans to follow through on his promise, but he is delaying the move so it won't hurt deal between Israel and the Palestinians. He said, "no one should consider this step to be in any way a retreat from the president's strong support for Israel and for the United States-Israel alliance."

"President Trump made this decision to maximize the chances of successfully negotiating a deal between Israel and the Palestinians, fulfilling his solemn obligation to defend America's national security interests," Spicer said. "But, as he has repeatedly stated his intention to move the embassy, the question is not if that move happens, but only when."

Some supporters had hoped Trump would announce the move during his visit to Israel last week.

"It would have been a great time for him to announce that promise to move the embassy to Jerusalem," former Arkansas Gov. Mike Huckabee said during a recent appearance on Fox News.

"I thought that he hit a single," Huckabee said. "He could have hit a home run. I think it's a missed opportunity."

Moving the embassy to Jerusalem would be seen as an aggressive move by the United States. While Jerusalem is the traditional capital of Israel, it has a complicated religious history due to it containing holy sites from the three major world religions. The city was split into eastern and western portions during the creation of the Israeli state in 1948 and the eastern portion, which was controlled by Jordan, was captured by Israel in 1967.