WASHINGTON (Reuters) -Large defense companies have "conned" the U.S. military into buying expensive equipment when cheaper commercial options would have been available, U.S. Army Secretary Dan Driscoll said.

Government accountability advocates and some lawmakers have long argued that defense contractors have overcharged the military. But Driscoll's comments were unusually blunt for a sitting government official speaking out against companies that supply the largest military in the world.

"(The) defense industrial base broadly, and the primes in particular, conned the American people and the Pentagon and the Army," Driscoll told reporters, referring to prime contractors that work directly with the government.

He added that, in part, it was the government's fault for creating incentive structures that encouraged companies to charge astronomical prices.

Large weapons makers provide the U.S. military with all types of systems, from Lockheed Martin's F-35 fighter jets to missile defense systems from companies like RTX, Northrop Grumman and Boeing.

Previously, the Army has said that a Lockheed-owned Sikorsky Black Hawk helicopter screen control knob that costs $47,000 as part of a full assembly could be manufactured independently for just $15.

"The system has changed. You will no longer be allowed to do that to the United States Army," Driscoll said.

The Army is launching an initiative to streamline its acquisition process. It is part of an overall effort by the Pentagon to allow the military to more rapidly acquire technology amid growing global threats.

Reuters reported last week that the U.S. Army is aiming to buy at least 1 million drones in the next two to three years and instead of partnering with larger defense contractors, it wants to work with companies that were producing drones that could have commercial applications as well.

Democratic U.S. Senator Elizabeth Warren this month escalated pressure on the defense industry to stop opposing military right-to-repair legislation.