Hadi Jallo Merei, the president of the Baghdad-based Journalistic Freedoms Observatory, told RFE/RL's Radio Free Iraq that the country's Communications and Media Commission has issued a list of 44 foreign and domestic media groups that are operating without proper registration.
The Interior Ministry has ordered police to enforce the closure of all companies on the list.
The list includes U.S.-funded Radio Sawa, an Arabic-language radio station operated by the Middle East Broadcasting Networks, a sister station to Radio Free Europe/Radio Liberty.
Radio Sawa says it does have a license. Deputy Director Salah Nasrawi told AP that he was surprised to see the station on the list but said it could be a bureaucratic error.
The Iraqi media commission has denied the measure is meant as a widespread crackdown against the press.
But press watchdog groups have accused Iraqi Prime Minister Nuri al-Maliki of seeking to muzzle the media in order to consolidate power.
The government has made no official response to the ordered closures.