WASHINGTON —The Secure World Foundation, a nonprofit organization dedicated to space sustainability, will close its Brussels office because of cost concerns, the organization announced Sept. 9.

“We have made wonderful progress in our relationship with European institutions dedicated to sustainable use of outer space,” Michael Simpson, the foundation’s executive director said in a press release. “But Brussels is a very expensive city and the challenges of supporting an office there proved to be more than we could sustain.”

Two staff members in the Brussels office were offered positions in the United States, but have decided to remain in Europe.

The foundation said it will remain active in Europe in advocating for an international code of conduct for space activities.