FRANKFURT (AFX) - The European Central Bank warned euro zone governments the growth assumptions for their budgets must be realistic, and said they must not use accounting tricks to exaggerate the health of fiscal positions. "It needs to be reemphasised that fiscal targets ... have to be based on realistic growth assumptions," the ECB said in its July monthly bulletin. "Any attempt to improve artificially the current budget positions by means of accounting measures should be resisted," it added. The ECB said only a "determined implementation" of the EU's stability and growth pact will ensure that its credibility remains intact. Italy was accused by Eurostat earlier this month of using accounting tricks to boost its budget, while France has made the target of balancing the budget in 2004 conditional on reaching growth rates of 3 pct.