President of the European Council extended his influence into financial policy, the most important area left to the rotating Council presidency, with the rotating presidency seeing a greater decrease in power than previously planned. Many of the changes introduced with the Lisbon Treaty need concretion through practical implementation by the current actors. The Spanish presidency unsuccessfully tried to challenge the European Council president's prominent post during the first rotating presidency of 2010, while the second half of the year saw a Belgian rotating presidency marked by a weakened caretaker government which did not challenge Herman van Rompuy, himself a Belgian politician. The Belgian rotating presidency
President of the European Council facing Europe, but was overtaken by the Greek economic crisis. The role of "President-in-Office" of the assembled European Council was performed by the head of state or government of the member state currently holding the Presidency of the Council of the European Union. This presidency rotated every six months, meaning there was a new President of the European Council twice a year. The role as President-in-Office was merely a "primus inter pares" role among other European heads of state or government. Being primarily responsible for preparing and chairing the meetings of the European Council, the role had no executive powers