The emergency budget, which will likely be followed by more spending packages later to fund reconstruction, includes about 1.6 trillion yen of infrastructure-related spending.

It will be submitted to parliament next week and is expected to be enacted in May.

Authorities are wary of adding to a massive public debt already twice the size of Japan's US$5 trillion economy, but additional bond issuance is likely for subsequent extra budgets that will be needed for rebuilding after the disaster, which has left nearly 28,000 dead or missing and triggered a major nuclear crisis.

Tokyo estimates the material damage alone could top US$300 billion in the world's costliest natural disaster.