Story highlights The foreign ministers say Iran is inciting unrest with its "hostile and provocative statements"

Protesters angry about a Shiite cleric's execution stormed the Saudi embassy in Tehran last weekend

Members of the Gulf Cooperation Council meet in Riyadh, agree to call embassy attack terrorism

Riyadh, Saudi Arabia (CNN) A six-nation Middle Eastern alliance agreed Saturday to characterize the recent attack on Saudi Arabia's embassy in Tehran as an act of terror -- strong language that marks an even further escalation in a tiff that has embroiled the region for days.

Foreign ministers from the six Gulf Cooperation Council met in the Saudi Arabian capital of Riyadh, after which alliance Secretary-General Abdul Latif Zayani read a statement indicating that the nations agreed to label last weekend's incident as terrorism.

Zayani himself a few days ago referred to the Saudi Embassy as a terrorist act, so this terminology isn't entirely new. Still, it is significant in that the six GCC countries -- Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates -- are now officially on the same page.

It also suggests countries in the region aren't acceding to requests from the United Nations, United States and other officials to tone down their rhetoric and refocus on other issues, like peacefully ending Syria's civil war and dealing with ISIS.

Iranian President: Anger over executions 'only natural'

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