The Japanese government aims to have an emergency budget for post-quake relief and reconstruction by the end of April, Finance Minister Yoshihiko Noda said on Friday.
Noda also said Japan should be careful about increasing its bond supply and that it will need a dedicated agency to lead government disaster relief efforts.
We cannot easily increase government bond issuance, Noda told reporters.
Ruling coalition officials have suggested that the government will try to seek savings and spending cuts in the regular budget to limit the need to borrow more.
Economics Minister Kaoru Yosano, speaking separately, told reporters that the government may need to reconsider its earlier plan to cut the corporate tax, given the reconstruction needs.
He also said the parliament would have to start debating an emergency budget within a month.
The government on Wednesday estimated the direct damage from a deadly earthquake and tsunami that struck the country's northeast this month at as much as $310 billion, making it the world's costliest natural disaster.
But with its debt already twice the size of its $5 trillion economy -- the highest among industrialized nations -- Japanese Finance Minister Yoshihiko Noda has warned the country should not rush to borrow to pay for the reconstruction.
Ruling party officials have said Tokyo will need two or more supplementary budgets to finance Japan's biggest rebuilding effort since the post-World War Two reconstruction.
Economists polled by Reuters this week forecast total public spending related to the disaster at up to almost $250 billion with forecasts ranging between 5 and 20 trillion yen