An Al-Jazeera cameraman held without charge at Guantanamo Bay has called for the release of the BBC Gaza's reporter, Alan Johnston, abducted two months ago.
Mr Hajj's relatives and employers have fought for his release
Sami al-Hajj, who has been accused of links to militant groups but not charged, has urged Muslims against copying the example set by the US.
"What the Americans are doing to me is very, very wrong," Mr Hajj writes in a letter released by his lawyer.
But he says no Muslim should put the journalist through the same suffering.
Mr Hajj, a 38-year-old journalist from Sudan, was working as a cameraman for Arab broadcaster Al-Jazeera when he was arrested by US forces in Afghanistan in 2001.
He has been accused of links to militant groups but has yet to be formally charged after more than five years of detention.
He has denied the allegations against him and his employers at Al-Jazeera say the charges are politically motivated.
In his letter, Mr Hajj urged Mr Johnston's abductors to set him free.
"As brothers in one faith, consider this gift that I request of you," he said.
"While the United States has kidnapped me and held me for years on end, this is not a lesson that Muslims should copy."
Alan Johnston, 45, was seized on 12 March in Gaza City on his way home from work.
There has been virtually no official news about Mr Johnston since his disappearance, despite Palestinian officials speaking frequently of prospects for his release.
More than 100,000 people have now signed an online petition calling for his release.