Japan and South Korea say North Korea has informed them it will close some air routes during its planned satellite launch next month.

The North sent notification to the International Civil Aviation Organization on Saturday, South Korea's Civil Aviation Safety Authority said. The authority says two routes will be closed.

The North has said it plans to launch a satellite sometime from April 4-8. Many regional powers are concerned, however, that the launch is a cover for a test of missile technology.

Japan's Transportation Ministry also reported the closure. The ministry said there are no planes scheduled to arrive in or depart from Japan that use the routes that North Korea is referring to.