BAGHDAD – Blackwater Worldwide, the security company accused of using excessive deadly force while protecting U.S. diplomats in Baghdad, would be barred from future work in Iraq under a decision by Baghdad officials to pull the firm’s security license.

“We have been informed that Blackwater’s private security company operating license will not be granted,” a U.S. Embassy official said Thursday. “We don’t have specifics about dates. We are working with the government of Iraq and our contractors to address the implications of this decision.”

The North Carolina company employs about 1,000 personnel in Iraq to safeguard U.S. State Department officials. But Blackwater security guards have been accused of being trigger-happy, most notably in a 2007 incident in which they killed at least 17 Iraqis while protecting a U.S. State Department motorcade.

At the time, the Iraqi government demanded that Blackwater be banned, but backed down when the U.S. Embassy approved the firm’s resumption of work activities.

Until the implementation of a joint security agreement between Iraq and the U.S. this month, private security firms were granted immunity from Iraqi criminal prosecution. Now, however, the companies lack immunity, and the Iraqi government has the authority to bar firms from operating in the country.

The Iraqi government could still overturn its new decision, and the overall status of independent security contractors in Iraq remains unclear.

Longtime observers said that the matter was probably still under negotiation between the Iraqi and U.S. governments.

Anne E. Tyrrell, a Blackwater spokeswoman, said the company had yet to be officially informed of the decision.

“Blackwater followed the proper procedures to apply for and secure operating licenses in Iraq. We have received no official communications from the government of Iraq or our customer on the status of those applications or the future of our work in Iraq,” Tyrrell said.

The announcement comes at a time when violence has dropped significantly across the nation, but also as federal prosecutors in the U.S. prepare to try five former Blackwater guards on manslaughter and weapons charges stemming from the Sept. 16, 2007, slayings.