Iran and the UAE are also embroiled in a territorial dispute over the sovereignty of three islands in the waterway.
Iran insists on calling the water along its southern coast the Persian Gulf. The body of water also touches Saudi Arabia, Kuwait, the UAE, Oman, Qatar and Bahrain, and these states refer to the waters as the Arabian Gulf.
Up to 200 people demonstrated at the UAE embassy to mark Iran’s annual National Persian Gulf Day, witnesses said. "Always Persian Gulf," one banner said. "Children of Iran are looking toward Bahrain," read another.
A hardline Iranian newspaper last year triggered protests in Bahrain, which has a majority Shia population, by saying it belonged to non-Arab Iran. The two countries later moved to defuse a potential diplomatic row.
In 2004, Iran banned National Geographic magazine when it included the Arabian Gulf name in parentheses on a map. The magazine later changed the labelling, a move Iranian officials described as "a victory for all Iranians".
Some news organisations use the Gulf as a compromise term.
