The establishment which in a given State is in charge of issuing bank notes and controlling the volume of currency and credit. In France, it is the Banque de France which assumes this role under the auspices of the European Central Bank (see ECB) while in the UK it is the Bank of England.
ECB : https://www.ecb.europa.eu/home/html/index.en.html
Banque de France : https://www.banque-france.fr/
Bank of England : http://www.bankofengland.co.uk/Pages/home.aspx