(2) When the estimates of expenditure (other than expenditure charged upon the Consolidated Fund by this Constitution or by any law enacted by Parliament) have been approved by the House, a bill, known as an appropriation bill, shall be introduced in the House, providing for the issue from the Consolidated Fund of the sums necessary to meet that expenditure and the appropriation of those sums, under separate votes for the several services required, to the purposes specified therein.