Japan says that North Korea's rocket launch earlier this week shows Pyongyang has made progress in developing its missile technology.

Japan's Chief Cabinet Secretary Takeo Kawamura told reporters Wednesday that while it is still unclear if the rocket was carrying a satellite, the launch took place in a way that was more advanced than previous attempts.

In a 2006 launch of North Korea's Taepodong-2 missile, the rocket blew apart seconds after its launch.  The North fired a shorter-range Taepodong-1 over Japan in 1998 as part of a failed satellite launch.

This time, the rocket soared over Japan and landed in the Pacific Ocean. Military analysts say Sunday's launch was effectively a test of a ballistic missile designed to carry a warhead as far as the U.S. state of Alaska.

North Korea insists it put a satellite into space, a claim dismissed by the U.S. military and South Korea.

Japan is demanding that the United Nations Security Council issue a strong response to the North Korean launch.

North Korea says it will take "strong steps" if the U.N. Security Council takes any action against its rocket launch.   

On Tuesday, diplomats representing the five permanent members of the Security Council (Britain, France, China, Russia and the United States) and Japan were scheduled to meet to discuss possible Council action against North Korea for Sunday's missile launch.  The meeting was canceled abruptly.

North Korea argues that it is "not fair" that other countries have been allowed to launch satellites, while North Korea is not allowed to do so.

U.S. officials have called on China and Russia to get tough with North Korea and threaten the country with sanctions.  

The United States and Britain are calling for a tough response to the launch.  China and Russia, which have veto power in the Security Council, are pushing for a more muted response.

Some information for this report was provided by AFP, AP and Reuters.