Israel's defense minister says Saudi Arabia has given Israel written assurances the kingdom will guarantee Israel freedom of passage in the Tiran Straits.
Tuesday's announcement comes as Egypt readies to hand over control of two islands in the straits to the kingdom.
Moshe Yaalon says an agreement was reached by which Saudi Arabia will continue to fulfill Egypt's commitment to free passage.
Israel and Saudi Arabia have no official relations, but ties have warmed recently mainly over shared concerns about Iran's growing influence in the region.
The two islands control entry to ports in Israel and Jordan. Access to the waterway was a factor in past wars.
Israel captured them in the 1967 Mideast war but returned them to Egypt after the two nations signed a peace treaty in 1979.