TEHRAN, Aug 17 (INP) One of Iran’s most prominent opposition leaders, under house arrest since 2011, began a hunger strike on Wednesday to demand a public trial, family members said. The release of the opposition leader, Mehdi Karroubi, and another former presidential candidate under house arrest, Mir Hossein Mousavi, was a major demand by supporters of President Hassan Rouhani during his re-election campaign. They shouted slogans in support of the two men during every campaign rally in May. The protest by Mr. Karroubi, 79, who has been hospitalized several times in recent months for heart problems, places Mr. Rouhani in a difficult position, as he has long vowed to get the two men released, The New York Times said in a report on Thursday. It is widely thought that Iran’s supreme leader, Ayatollah Ali Khamenei, opposes their release and objects to a trial. The two men have never been formally charged. Mr. Karroubi, a cleric and a former speaker of Iran’s Parliament, and Mr. Mousavi, a former prime minister, both ran for president in the disputed 2009 election. After the incumbent at the time, Mahmoud Ahmadinejad, declared victory, huge street protests rocked Tehran, the capital, and other cities in what became known as the Green Revolution. Mr. Karroubi and Mr. Mousavi emerged as its unofficial leaders. Two years after the protests, when they continued challenging the establishment, both men and Mr. Mousavi’s wife, Zahra Rahnavard, were placed under house arrest. Mr. Karroubi’s son, Mohammad Taghi Karroubi, announced the hunger strike in a Twitter posting, saying his father demanded that security guards leave his apartment and that a date be set for a public trial in accordance with Iran’s Constitution. Mr. Karroubi’s wife, Fatemeh Karroubi, said he was not even drinking water. “After an advice by a doctor designated by the Intelligence Ministry and my insistence, he only took his heart medication today and refused to eat or drink,” Mrs. Karroubi was quoted as saying by the Saham news website, which is affiliated with the Karroubi family. INP/AH/LK