North Korea might be considering a nuclear test near the time the U.S. presidential election is held to raise its profile, South Korea’s defense minister said, as Kim Jong Un rolls out new warheads capable of striking the U.S. and its allies in Asia.

Seoul will reach a deal with Japan and the U.S. to standardize the tracking of missiles fired from North Korea, Shin Wonsik said in an interview on Sunday in Tokyo.

He was visiting the Japanese capital to sign a deal with the U.S. and Japan to lock in gains in security cooperation that have included joint military training.