An executive authority shall enter into a collective agreement in the appropriate bargaining council on any matter that has financial implications only if—
| (a) | he or she has a realistic calculation of the costs involved in both the current and the subsequent fiscal year; |
| (b) | the agreement does not conflict with the Treasury Regulations; and |
| (c) | he or she can cover the cost— |
| (i) | from his or her departmental budget; |
| (ii) | on the basis of a written commitment from the Treasury to provide additional funds; or |
| (iii) | from the budgets of other departments or agencies with their written agreement and Treasury approval. |
