President Joe Biden ordered the Pentagon to send the Terminal High Altitude Area Defense system — known as THAAD — to Israel in the coming days to help Israel fend off potential Iranian missile attacks and add to the Israeli government’s already robust missile defense infrastructure.

The move “underscores the United States’ ironclad commitment to the defense of Israel, and to defend Americans in Israel,” Pentagon spokesperson Maj. Gen. Patrick Ryder said in a statement Sunday.

The ground-based system that can shoot down ballistic missiles is the latest in a steady buildup of U.S. forces in the region as Israel and Iran have engaged in the most significant rounds of strikes against each other in their histories, deepening fears of a wider regional war.

Iran has already launched hundreds of ballistic missiles and drones at Israel in two attacks in April and October, which the Israelis have largely defeated with the help of the U.S., United Kingdom and France, as well as other countries in the region.