Institutional seats of the European Union are based in Luxembourg City along with the European Investment Bank. The Economic and Social Committee and the Committee of the Regions are entirely based in Brussels while the European Central Bank is based in Frankfurt and Europol is the only agency to have its seat fixed by the treaties, in The Hague. Separately, the Treaty of Nice establishes Brussels as the venue for all formal summits of the European Council after 2004. However some extraordinary sessions are sometimes held outside the city. The European Council's seat is however fixed by a declaration rather than a protocol, meaning it is
Institutional seats of the European Union locations of the major seats have been enshrined in the treaties of the European Union, Parliament has no right to decide its own seat, unlike other national parliaments. Locating new bodies is also not without political disputes. The European Central Bank's (ECB) seat had to symbolise its independence from political control, and was located in a city which did not already host a national government or European institution. New agencies are also being based in eastern Europe since 2004 to balance the distribution of agencies across the EU. The treaties of the European Union outline the locations of the following