WASHINGTON, May 12 (UPI) — The U.S. Senate has passed a resolution calling on Iran to immediately release Jason Rezaian, a Washington Post journalist, Saeed Abedini a Christian pastor and Amir Hekmati, a former marine.

The resolution passed with a unanimous vote on Monday. The Senate hopes the resolution would mount on pressure currently on Iran, setting the stage for the release of detainees.

Rezaian was charged in April by Iran with four crimes, including espionage, which could carry a 20-year prison sentence.

Abedini was sentenced to eight years imprisonment on charges of undermining national security. Hekmati is accused of espionage.

“Iran has a long track record of arresting Americans and using trumped-up charges to hold them,” Sen. Debbie Stabenow, D-Mich., said. “[Hekmati] is a hero who proudly served his country.”

The resolution calls for Iran to “cooperate with the United States Government to locate and return” former FBI agent Robert Levinson, who disappeared in 2007 while in Iran.

The resolution also calls on the White House to “undertake every effort using every diplomatic tool at its disposal” to see the American men released.

“One of those Americans, Saeed Abedini, has reportedly been held prisoner for what would appear to be the supposed ‘crime’ of attempting to build and operate an orphanage,” Senate Majority Leader Mitch McConnell, R-Ky., said on the Senate floor. “Beaten, denied access to medical care, and locked away in solitary confinement — that’s apparently how the Iranian regime deals with those who dare to show love and compassion to others.”