North Korea said Wednesday it will permanently block its border with South Korea and build front-line defense structures to cope with “confrontational hysteria” by South Korean and U.S. forces, while not announcing an expected constitutional revision to formally designate South Korea its principal enemy and codify new national borders.

While the moves were likely a pressure tactic, it’s unclear how they will affect ties with South Korea since cross-border travel and exchanges have been halted for years.

North Korea’s military said it will “completely cut off roads and railways” linked to South Korea and “fortify the relevant areas of our side with strong defense structures,” according to the North’s official Korean Central News Agency.