Vice President Mike Pence assured thousands of Christian supporters of Israel on Monday that it’s only a matter of time until President Donald Trump moves the U.S. Embassy from Tel Aviv to Jerusalem. Pence was the guest speaker at the annual Christians United for Israel’s ‘Night to Honor Israel’ in Washington, D.C.

“I promise you that the day will come when President Donald Trump will move the American Embassy from Tel Aviv to Jerusalem,” Pence said to loud applause. “It is not a question of if, it is only when.”

Pence also reassured the crowd that while certifying Iran’s compliance with the 2015 nuclear deal, the President “will not allow Iran develop a usable nuclear weapon. This is our solemn promise to the American people, to the people of Israel and to the world.”

The Vice President added that the terms of President Barack Obama’s Iran deal are still under review and that the administration “will no longer tolerate” Iran’s effort to destabilize the Middle East region and threaten Israel.