A renewed claim by the emirates prompted Mahmoud Ahmadinejad to make a surprise visit to the 4-mile-square island recently, the first by an Iranian president, The New York Times reported Tuesday.
The move prompted angry reaction from Arab states on the western shore of the Persian Gulf but drew approval at home for Ahmadinejad.
"Be sure that Ahmadinejad saw those angry Arab reactions coming," one woman who declined to give her name told the Times. "He needs distraction from his internal problems."
A 1971 memorandum of understanding between Iran and the emirate of Sharjah stipulates the island and its energy resources are to be divided evenly between the two.
Most of the inhabitants of Abu Musa have been Arab for centuries, the United Arab Emirates said, but Iran contends the island was Iranian territory until Britain occupied it in 1908.
Tensions in the Persian Gulf are always high but the dispute over Abu Musa has taken on added significance due to recent weapon purchases by Saudi Arabia and the emirates worth more than $100 billion.