Foreign ministers from Gulf Cooperation Council (GCC) states will hold an extraordinary meeting in Riyadh on 9 January to discuss increasing tension with Iran after Saudi missions there were attacked.

“Foreign ministers of the GCC States will hold an extraordinary meeting in Riyadh on Saturday… to discuss the repercussions of the attack on the Embassy of Saudi Arabia in Tehran and the Saudi consulate in the Iranian city of Mashhad,” news agency Reuters cited GCC secretary-general Abdullatif bin Rashid al-Zayani as saying in a statement.

The attack on the Saudi embassy in Tehran was a response by demonstrators to the 1 January execution of prominent Saudi Shia cleric Nimr al-Nimr – a vocal proponent of rights for the Saudi Arabia’s minority Shia population.

Saudi Arabia severed diplomatic ties with Iran in response to attacks on its missions. Bahrain and Sudan, close allies of the kingdom followed suit, while the UAE downgraded relations and Kuwait recalled its ambassador to Tehran in a diplomatic crisis that could deepen sectarian tension in the war-torn Arab world.

Tensions between Saudi Arabia and Iran, the two oil producing Persian Gulf power houses, threaten to derail efforts to end Syria’s five-year-old civil war in which Saudi Arabia and its Gulf Arab allies back rebel groups against Iranian-backed Syrian President Bashar al-Assad.

They also cast doubts over chances for a peaceful solution in Yemen, where a Saudi-led military coalition has been bombing the Iran-allied Houthi movement for nine months, according to Reuters.