decis common accord govern member state adopt euro level head state govern appoint member execut board european central bank ec head state govern member state european commun adopt euro chairmanship mr costa simiti presid govern hellen republ regard treati establish european commun articl articl protocol statut european system central bank european central bank regard recommend council regard opinion european parliament regard opinion govern council european central bank decid articl ms gertrud tumpel gugerel appoint member execut board european central bank term offic year appoint take effect june articl decis publish offici journal european union brussel presid simiti oj opinion publish offici journal oj