The former world heavyweight boxing champion Muhammad Ali has asked Iran to release two American hikers held since 2009 on charges of spying.
Muhammad Ali, arguably the most prominent US Muslim, sent a letter to supreme leader Ayatollah Ali Khamenei in February and released it publicly yesterday to the Associated Press news agency.
The letter asks the Ayatollah to release Josh Fattal and Shane Bauer, who were arrested while hiking in northern Iraq near the Iranian border. A third hiker, Sarah Shourd, was released on bail in September, shortly after Ali first wrote to Khamenei.
The three met while studying at the University of California at Berkeley. Mr Fattal joined the other two in Damascus, where they were living at the time, and they set off for what they and friends insist was a perfectly innocent walking expedition. The falls on the border, though remote, are famous for their beauty.
The predicament of the accused men is complicated by America's deeply strained relations with Iran.
The US Secretary of State Hillary Clinton has repeatedly called for Iran to release the prisoners.
Ali's letter asks Ayatollah Khamenei as a brother in Islam to show the same mercy and compassion for the two men. Ali founded his centre for world peace in Louisville, Kentucky, where he grew up and launched a career that included three world heavyweight titles.