WASHINGTON, March 16 (Reuters) - Secretary of State Marco Rubio has designated as wrongfully detained in Iran 61-year-old Jewish ‌Iranian-American Kamran Hekmati, his cousin said on Monday.

"This designation ‌is an official recognition by the U.S. Government that Kamran is being held ​on false charges in an effort by the Iranians to leverage the U.S. Government," Shohreh Nowfar said in a statement.

Word of the designation comes as the U.S.-Israeli war on Iran rages for its ‌third week.

The Office of ⁠the Special Presidential Envoy for Hostage Affairs did not immediately respond to a request for comment.

The ⁠designation of wrongfully detained means that an American citizen is considered a political hostage whose case is handled by SPEHA and whose ​release is ​given high-level diplomatic attention and ​specialized resources.

The designation "reassures us ‌that our government has our back in the effort to get Kamran home safely," Nowfar said.

Hekmati, who is suffering from bladder cancer, is one of at least six U.S. citizens or permanent residents being detained by Iran. He has been held in ‌Tehran's notorious Evin Prison, according to ​detainee advocates.

The jewelry shop owner was arrested ​last year and convicted ​of visiting Israel under a law that bars ‌such visits in the past ​10 years, even ​though he had documentation showing his last trip was 13 years before his arrest, according to Kieran Ramsey, a ​former FBI assistant ‌director with the Global Reach advocacy group who represents the ​Hekmati family.

(Reporting by Jonathan Landay in Washington; Editing by ​Chris Reese and Matthew Lewis)