Japan has failed to create a revamped nuclear regulatory agency by the promised date April 1 amid political infighting, raising questions about its commitment to bolstering oversight after last year's nuclear crisis.

Authorities have been accused of lax supervision of Japan's 54 nuclear reactors after a massive earthquake and tsunami led to a meltdown of three reactors at the Fukushima Daiichi plant in the world's worst nuclear disaster since Chernobyl. Prime Minister Yoshihiko Noda's Cabinet has endorsed a bill to create a more powerful and independent regulatory body that would unify various nuclear safety and regulatory agencies. But progress has been slowed by disagreements over how much independence it should have.

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