What is the country between red sea and Persian gulf has largest known petroleum?

The country between the Red Sea and the Persian Gulf that has the largest known petroleum reserves is Saudi Arabia. Saudi Arabia is located in the Middle East and is bordered by the Red Sea to the west and the Persian Gulf to the east. It is the largest country on the Arabian Peninsula and has the second largest proven oil reserves in the world, after Venezuela. Saudi Arabia is a major oil exporter and a founding member of the Organization of the Petroleum Exporting Countries (OPEC).