Israeli Defense Minister Moshe Ya’alon said that Israel has signed off on a recent agreement between Egypt and Saudi Arabia to exchange sovereignty of two strategic islands at the entrance of the Gulf of Aqaba.

“An appeal was made to us—and it needed our agreement, [and the agreement of] the Americans, who were involved in the peace agreement and of the MFO (Multinational Force and Observers),” Ya’alon said, referring to the United Nations’ Multinational Force and Observers peacekeeping force in Egypt’s Sinai Peninsula, Haaretz reported.

“We reached an agreement between the four parties—the Saudis, the Egyptians, Israel, and the United States—to transfer the responsibility for the islands, on condition that the Saudis fill in the Egyptians’ shoes in the military appendix of the peace agreement,” said Ya’alon.

Saudi Arabia’s King Salman recently made a five-day visit to Egypt, where it was announced that Egypt would hand over sovereignty of the Red Sea islands of Tiran and Sanafir to Saudi Arabia, while the Saudis will provide $16 billion in aid to Egypt.

The uninhabited islands that sit on the southern entry to the Gulf of Aqaba were originally given to Egypt in 1950 by Saudi Arabia, in order to protect them from Israel. Later, the islands played an important role in setting off the 1967 Six-Day War when Egypt closed the Straits of Tiran to Israeli ships, thereby preventing Israeli access to the Red Sea and Indian Ocean. As a result, United Nations peacekeepers maintain a presence on Tiran as part of the 1979 Israel-Egypt peace treaty.