Read this: The primary objective of the European Central Bank, as mandated in Article 2 of the Statute of the ECB, is to maintain price stability within the Eurozone. The basic tasks, as defined in Article 3 of the Statute, are to define and implement the monetary policy for the Eurozone, to conduct foreign exchange operations, to take care of the foreign reserves of the European System of Central Banks and operation of the financial market infrastructure under the TARGET2 payments system and the technical platform (currently being developed) for settlement of securities in Europe (TARGET2 Securities). The ECB has, under Article 16 of its Statute, the exclusive right to authorise the issuance of euro banknotes. Member states can issue euro coins, but the amount must be authorised by the ECB beforehand.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): What restricts ECB the right to authorise the issuance of euro banknotes?
unanswerable