Art. 123(1) TFEU prohibits the ECB and the central banks of the Member States from granting overdraft facilities or any other type of credit facility to public authorities and bodies of the European Union and of Member States and from purchasing their debt instruments directly from them (CJEU, Judgment of 16 June 2015, Gauweiler, C-62/14, EU:C:2015:400, para. 94). Nevertheless, the Eurosystem is not, generally, precluded from purchasing bonds previously issued by a Member State from the creditors of that Member State (cf. CJEU, loc. cit., para. 95). Thus, Article 18.1 of the ESCB Statute permits the ESCB, in order to achieve its objectives and to carry out its tasks, to operate in the financial markets, inter alia , by buying and selling outright marketable instruments, which include government bonds, and does not make that authorisation subject to particular conditions as long as the nature of open market operations is not disregarded (cf. CJEU, loc. cit., para. 96). Nevertheless, the ESCB does not have authority to purchase government bonds on secondary markets under conditions which would, in practice, mean that its action had an effect equivalent to that of a direct purchase of government bonds from the public bodies and institutions of the Member States, thereby undermining the effectiveness of the prohibition in Article 123(1) TFEU. (cf. CJEU, loc. cit., para. 97). The objective of Article 123 TFEU is to encourage the Member States to follow a sound budgetary policy, by not allowing monetary financing of public deficits or privileged access by public authorities to the financial markets to lead to excessively high levels of debt or excessive Member State deficits (cf. CJEU, loc. cit., para. 100). It is not permissible to resort to purchases on the secondary market in order to circumvent the objective pursued by Art. 123 TFEU (CJEU, loc. cit., para. 101). Therefore, any programme relating to the purchase of government bonds on the secondary market must provide sufficient guarantees to effectively ensure observance of the prohibition of monetary financing (cf. CJEU, loc. cit., paras. 102 et seq.). Market operators who would potentially purchase government bonds on the primary market must not know for certain that the ESCB is going to purchase those bonds within a certain period and under conditions allowing these market operators to act, de facto, as intermediaries for the ESCB for the direct purchase of those bonds (cf. CJEU, loc. cit., para. 104). Therefore, the Member States may not, in determining their budgetary policy, be afforded certainty that the ESCB will at a future point purchase their government bonds on secondary markets (cf. CJEU, loc. cit., para. 113). In addition, a minimum period must be observed between the issue of a security on the primary market and its purchase on the secondary market. Any prior announcement concerning either the ESCB’s decision to carry out such purchases or the volume of the envisaged purchases must be ruled out (cf. CJEU, loc. cit., para. 106). Purchased bonds may only in exceptional cases be held until maturity (cf. CJEU, loc. cit., paras. 117 and 118). Lastly, purchases must be limited or suspended, and purchased bonds must be remarketed, should continuing the intervention or further holding the bonds no longer be necessary for achieving the monetary policy objectives (cf. CJEU, loc. cit., paras. 112 et seq., paras. 117 et seq.).