A controversial arms deal for Arab allies approved by the Trump administration will allow U.S. hi-tech bomb parts to be manufactured in Saudi Arabia, giving Riyadh unprecedented access to a sensitive weapons technology.

The production arrangement is part of a larger $8.1 billion arms package for Saudi Arabia, the United Arab Emirates and Jordan announced two weeks ago. The Trump administration pressed ahead with the sale without congressional approval, declaring an “emergency” based on what it said was a heightened threat from Iran.

The deal came as a surprise to lawmakers, who were outraged that the administration chose to bypass Congress. But most members of Congress only learned days after the deal was announced May 24 that it opens the door for Saudi Arabia to host the production of electronic guidance and control systems for Paveway precision-guided bombs, congressional aides said.