(CNN) -- The families of two American hikers set to stand trial this week on charges of spying called on Tehran Monday to release the men.
Shane Bauer and Josh Fattal, who have been jailed in Iran since 2009, are set Wednesday to answer charges of illegal entry and espionage -- charges that can carry the death penalty.
The case has been delayed twice before because a third American defendant, Sara Shourd, has not appeared in court to face similar charges.
"For more than 21 months, Shane and Josh have been locked up, isolated from their families and the world and denied any semblance of due process," the families said in a statement.
"The charges they face are as cynical, unjust and unreasonable as the length of their incarceration and it is time for Iranian judicial authorities to stop playing games with their lives."
The three graduates of the University of California at Berkeley had been hiking together in Iraq's Kurdistan region when they were detained by Iranian border forces on July 31, 2009, for allegedly crossing into Iran illegally. They have pleaded not guilty.
In September, after 14 months in prison, 32-year-old Shourd was released on $500,000 bail because of a medical condition.
She has since said she will not return to Tehran, citing depression and post-traumatic stress disorder caused by her imprisonment.
Iranian authorities have said Shourd, who is engaged to Bauer, will be tried in absentia if she doesn't show.
"More than anything, I want Shane and Josh to be free," said Shourd according to an article written last year by Shourd for CNN.
U.S. officials and others have repeatedly called for the release of Bauer and Fattal, both 28.
Archbishop Desmond Tutu of South Africa was the latest to ask Iran to release the two men, calling their detention "morally unacceptable."
"There is no evidence to support the charges against them," Tutu said in a written statement released over the weekend.
The families called on "authorities to take this opportunity to end the mistreatment of two young men who have done no wrong to Iran and mean more to us than anything."
The two men, who share a 10-by-14-foot cell, have not spoken to their families since November, according to freethehikers.org, a website dedicated to freeing the two men. Nor have they had access to their Iranian lawyer, it added.
Their Iranian lawyer, Masoud Shafii, has said all three pleaded not guilty. According to Iranian law, he has said the cases "should be separated so the trials can go on."
CNN's Augie Martin contributed to this report.