SEOUL (Reuters) - Isolated and impoverished North Korea launched its second long- range rocket of 2012 on Wednesday in what it said was a bid to put a satellite into space.

The North launched the rocket close to the first anniversary of the death of former leader Kim Jong-il and as elections loom in South Korea and Japan.

The launch, reported by South Korean media, was confirmed by South Korea's Defense Ministry.

Pyongyang says it is entitled to launch a satellite into space but critics say the rocket development is aimed at nurturing the kind of technology needed to mount a nuclear warhead on a long-range missile.

North Korea is banned from conducting missile and nuclear-related tests under U.N. sanctions imposed after its 2006 and 2009 nuclear tests.

The latest launch comes after a failed attempt in April that fizzled less than two minutes after blast-off.

Japan and South Korea put their armed forces on alert prior to the launch. The rocket is scheduled to pass between the Korean peninsula and China, with a second stage splashing down off the Philippines before launching the satellite into orbit.

Most political analysts believe the launch is designed to bolster the credentials of new leader Kim Jong-un as he cements his rule over the country of 22 million people.

A government official in Seoul said recently that the transition of power to Kim Jong-un did not appear to be going as smoothly as anticipated and there were signs that the regime was concerned over the possibility of rising dissent.

Kim is the third of his line to rule North Korea, whose national output is around one-fortieth of that of prosperous South Korea.

Plans for the launch has drawn criticism from South Korea, Russia, Japan and the United States as well as NATO and the United Nations.

The North's only major diplomatic ally, China, has expressed "deep concern" over the launch but is thought unlikely to back any further sanctions against its ally.

(Writing by David Chance; Editing by Raju Gopalakrishnan)