According to Saudi officials, the alliance includes 14 countries, among them the Gulf states of Kuwait, Qatar and Bahrain as well as Pakistan, Turkey, Egypt and Jordan.
The alliance aims to protect freedom of navigation and international trade routes and global energy supplies, the Saudi defence ministry announced on Thursday in Riyadh after a meeting on the alliance.
The announcement follows attacks by the Iran-aligned Houthi militia in Yemen against Saudi ships.
The militia had already launched a series of attacks on merchant vessels in the Red Sea starting in 2023.
In response, the European Union-led Aspides mission and the United States-led Prosperity Guardian operation were established to protect shipping.
"Maritime security is a shared responsibility," the ministry stated.
This will be achieved through joint military operations, planning and exercises, and the exchange of intelligence.
The alliance is, by its very nature, "purely defensive" and does not aim to attack any country, other alliance or international organisation.
Due to the de facto blockade of the Strait of Hormuz, Saudi Arabia currently exports some of its oil to the Red Sea via a pipeline.
However, renewed attacks by the Houthi rebels are making this export route less secure.
It is noteworthy that, according to the announcement, Oman and the United Arab Emirates are not participating even though they share similar security objectives in the Iran conflict with Saudi Arabia.
Iranian Foreign Minister Abbas Araqchi urged Bulgaria to reconsider its decision to allow the temporary deployment of US military aircraft at its Bezmer air base, Iranian state media reported on Thursday.
During a phone call with his Bulgarian counterpart, Velislava Petrova-Chamova, Araqchi said Bulgraria's approval of a US request to station military aircraft at the base to support military operations amounted to facilitating aggression against Iran, adding the move was unacceptable and contrary to the traditionally friendly relations between the two countries.
Iran has repeatedly warned countries allowing their territory to be used for USmilitary operations against it that they could "face consequences".
Araqchi held a separate phone call with Cypriot Foreign Minister Constantinos Kombos, during which he stressed the importance of preventing foreign military bases in Cyprus from being used against Iran.
Bulgaria's parliament last week approved the temporary deployment of up to eight US KC-135 tanker aircraft and up to 250 personnel at Bezmer air base despite Iranian objections.
Bulgaria has said no offensive weapons would be deployed and that the move did not make the country a party to military operations.
Cyprus hosts two UK sovereign military bases including RAF Akrotiri, which was struck by an Iranian drone in early March a few days after Israel and the US initiated strikes on Iran.
The United Kingdom agreed early on in the war to a US request to use UK bases for defensive strikes against Iranian missiles in storage depots or launchers.
This arrangement was maintained by new UK Prime Minister Andy Burnham in July, prompting Iran's Revolutionary Guards to warn the UK against facilitating US military operations against Iran.
with Reuters
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