South Korea and the United States will kick off their annual joint military drills this week but without mobilizing U.S.-based troops after scaling back the program due to coronavirus concerns, South Korean media reported on Wednesday.

The allies have been discussing how to adjust the exercises, which usually begin in August, with the coronavirus threatening to disrupt the travel of U.S. personnel.

The program involves tens of thousands of soldiers from both sides, though largely focused on computerized simulations rather than live field training.