The decision by the strategic Horn of Africa nation came months after Shia-dominated Iran and Sunni-majority Saudi Arabia resumed relations under a China-brokered deal announced in March.
Iran and Saudi Arabia posted ambassadors to their respective diplomatic missions on Tuesday in a sign of warming relations that follow seven years of bitter rivalry.
Arab countries gathered in Jeddah on Friday to discuss ending Syria's long spell in the diplomatic wilderness, as regional relations shift following Saudi Arabia and Iran's decision to resume ties. Ministers and top officials from the six Gulf Cooperation Council countries Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates plus Egypt, Iraq and Jordan have arrived in Saudi Arabia at the kingdom's request, the foreign ministry said.