Authorisation of expenditure from Consolidated Revenue Fund
Section 81(4)(b) · 1999 Constitution (2004 edition)
What Constitution says
(b) a need has arisen for expenditure for a purpose for which no amount has been appropriated by the Act, a supplementary estimate showing the sums required shall be laid before each House of the National Assembly and the heads of any such expenditure shall be included in a Supplementary Appropriation Bill.
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 52. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections