WASHINGTON -- Executives from 25 news organizations, including The Associated Press, sent a letter Friday to Secretary of State John Kerry urging him to press Iran to release jailed Washington Post reporter Jason Rezaian.

The letter said Iran should recognize that independent journalism is "a fundamental human right" and free Rezaian. "The United States has considerable leverage with Iran right now to press that point, and we urge you to continue to do so," the executives wrote.

Rezaian, 39, was born in California and holds both U.S. and Iranian citizenships. He was convicted in closed proceedings last year after being charged with espionage and related allegations. The length of his sentence has not been disclosed publicly.

"Iran has never offered any evidence that even makes a pretense of justifying this imprisonment," the news executives wrote.

They noted: "Many of our organizations employ journalists who, like Jason, operate in countries, like Iran, that do not always hold a high regard for the free flow of information. We understand the risks involved."

Still, the letter continued, "we depend on the United States and other democratic countries to stand behind the values that Jason represents."

Media organizations represented in the letter included the AP, The New York Times, The Los Angeles Times, ABC, CBS, NBC and CNN.

The Post has vigorously denied the accusations against Rezaian. Post Publisher Frederick J. Ryan Jr. said in December that the United States, other governments and businesses should keep Rezaian in mind when considering improved relations with Iran.

"If the callous regime in Tehran imprisons and abuses a fully accredited and innocent journalist, what might they do to a visiting delegation?" Ryan said.