The United States has dismissed North Korea’s threat over the annual Ulchi Freedom Guardian military exercise between the U.S. and South Korea.

State Department Spokeswoman Victoria Nuland told reporters on Thursday that “there is nothing provocative, nothing unusual, nothing nontransparent about this exercise.”

She said the U.S. and South Korea conduct the joint military drills every year, and that every year, the North complains.

Nuland said the joint drills are “designed to enhance interoperability and the readiness of alliance forces to respond to any threats, so these are defensive in nature.” She then urged North Korea to exercise restraint.

Nuland’s remarks come after the North pledged to boost its nuclear deterrent as it denounced the joint military drills in a statement issued by its Foreign Ministry.