The group led by wanted Jordanian terrorist Abu Musab al-Zarqawi has pledged allegiance to Osama bin Laden's al-Qaida network.
In a statement posted Sunday on an Islamist Web site, the Tawhid and Jihad group said that with the start of the holy month of Ramadan, it is time for Muslims to unite against what it calls the enemies of Islam.
The authenticity of the statement could not be verified. But the United States has long said Zarqawi's group was linked to al-Qaida. Zarqawi's group has claimed responsibility for attacks on U.S. forces in Iraq and the kidnapping and executions of foreigners there.
Jordan has also charged Zarqawi and 12 others for plotting to attack several targets in Jordan with chemical weapons and explosives.
Information for this report is provided by AP and Reuters.