The condemnation came in the closing statement of the six-member Gulf Cooperation Council (GCC) foreign ministers' meeting in the Saudi port city of Jeddah.
"The ministerial council condemns Iran's establishment of two administrative offices on Abu Musa island that belongs to the UAE and demands that Iran remove these illegal installations and respect the UAE's sovereignty on its land," the GCC statement read. Abu Musa and the Greater and Lesser Tunbs, located near key shipping lanes in the Gulf, are controlled by non-Arab Iran but claimed by the United Arab Emirates with broad Arab support.
Iran's foreign ministry spokesman Hassan Qashqavi was quoted by Iran's Mehr News Agency on Wednesday as saying the GCC "statement is interfering in Iran's internal affairs and is rejected," adding that the islands would forever belong to Iran.
Qashqavi insisted that all the actions taken by Iran on Abu Musa were legal and based on Iran's rights over the island, calling on Gulf countries to be "realistic".
The UAE summoned Iran's charge d'affaires last month to protest against Iran's establishment of maritime offices on one of the islands and said the move should be reversed.
In May, the UAE protested against Iran's dismissal of the three-decade-old territorial dispute as a misunderstanding and said Iran was occupying the islands. A UAE source compared Iran's actions at the time to Israel's occupation of Arab lands.
The GCC foreign ministers called for a peaceful resolution of the dispute through direct negotiations or by referring the case to the International Court of Justice.
"(We) express regret for the failure of contacts with the Islamic Republic of Iran to reach any positive outcome towards a resolution to the issue of the three islands, which would bolster the stability and security of the region," it said.
The GCC is a loose bloc of Gulf Arab countries comprising the UAE, Saudi Arabia, Kuwait, Qatar, Oman and Bahrain. (Reporting by Lin Noueihed in Dubai and Edmund Blair in Tehran; Editing by Dominic Evans)
