BlackBerry Z10 and Q10 smartphones have made a "critical step forward in the security certification process" by the U.S. Department of Defence.

The phones now have what is called the authority to operate on Pentagon networks after approval by the U.S. Defence Information System Agency, BlackBerry announced in a news release Thursday.

That makes them the first smartphones to be supported on the U.S. defence network, said Scott Totzke, senior vice-president of the company's BlackBerry Security Group, in a statement.

"Receiving the ATO is a critical step forward in the security certification process," the news release said. "The approval demonstrates that BlackBerry 10 smartphones meet DoD's most stringent security requirements."

According to BlackBerry, DISA is designing the capacity to support 10,000 BlackBerry 10 smartphones by this fall and 30,000 by the end of 2013 on department networks.

However, there was no indication that the department had ordered any phones.

BlackBerry was once widely used by U.S. federal departments and agencies. However, many have been switching to other brands, such as Apple, in recent years.

Last October, the U.S. Immigration and Customs Enforcement Agency, a division of America's Department of Homeland Security, announced it would be moving away from solely using BlackBerry devices for the department's 17,676 employees.

A month later, the National Transportation Safety Board announced that it was dropping BlackBerry smartphones in favour of the new iPhone 5, saying the BlackBerry devices had been "failing both at inopportune times and at an unacceptable rate."