The Maastricht Treaty built upon the Single European Act and the Solemn Declaration on European Union in the creation of the European Union. The treaty was signed on 7 February 1992 and came into force on 1 November 1993. The Union superseded and absorbed the European Communities as one of its three pillars. The first Commission President following the creation of the EU was Jacques Delors, who briefly continued his previous EEC tenure before handing over to Jacques Santer in 1994.