The International Atomic Energy Agency (IAEA) said Friday its inspectors have departed Tehran and arrived safely to Vienna after Iran suspended cooperation in the wake of attacks on its nuclear program by Israel and the United States.

The withdrawal of international inspectors comes amid heightened concerns that Iran, battered by Israeli and U.S. strikes, may be driven to try to build a nuclear bomb.

The move intensifies a standoff over Iran’s nuclear work following Tehran’s decision to suspend cooperation with the agency.