(1) The Governor shall cause to be prepared and laid before the House of Assembly at any time before the commencement of each financial year estimates of the revenues and expenditure of the State for the next following financial year.
(2) The heads of expenditure contained in the estimates, other than expenditure charged upon the Consolidated Revenue Fund of the State by this Constitution, shall be included in a bill, to be known as an Appropriation Bill, providing for the issue from the Consolidated Revenue Fund of the State of the sums necessary to meet that expenditure and the appropriation of those sums for the purposes specified therein.
(3) Any amount standing to the credit of the judiciary in the Consolidated Revenue Fund of the State shall be paid directly to the heads of the courts concerned.
(4) If in respect of any financial year, it is found that -
(a) the amount appropriated by the Appropriation Law for any purpose is insufficient; or
(b) a need has arisen for expenditure for a purpose for which no amount has been appropriated by the Law,
a supplementary estimate showing the sums required shall be laid before the House of Assembly and the heads of any such expenditure shall be included in a Supplementary Appropriation Bill.
Section 121 of the Constitution of the Federal Republic of Nigeria