Languages of the European Union which is understood by 51% of all adults, while German is the most widely used mother tongue, spoken by 18%. All 24 official languages of the EU are accepted as working languages, but in practice only two – English and French – are in wide general use and of these English is the more commonly used. French is an official language in all three of the cities that are political centres of the Union: Brussels (Belgium), Strasbourg (France) and Luxembourg City (Luxembourg). , the official languages of the European Union, as stipulated in the latest amendment of "Regulation No 1
Institutional seats of the European Union less binding than the other seats. The 2011 Treaty Establishing the European Stability Mechanism (ESM) states that the seat of the ESM must be in Luxembourg. The ESM should be ratified and active in mid-2013 and it is allowed to establish a liaison office in Brussels. There are numerous other bodies and agencies that have not had their seats fixed by treaties. Brussels hosts the European Defence Agency (as NATO and formerly the WEU are also in the city). Luxembourg hosts the Translation Centre for the Bodies of the European Union and the European Investment Bank. Strasbourg and Brussels both