José Manuel Barroso became president in 2004: the Parliament once again asserted itself in objecting to the proposed membership of the Barroso Commission. Owing to this opposition, Barroso was forced to reshuffle his College before taking office. The Barroso Commission was also the first full Commission since the enlargement in 2004 to 25 members; hence, the number of Commissioners at the end of the Prodi Commission had reached 30. As a result of the increase in the number of states, the Amsterdam Treaty triggered a reduction in the number of Commissioners to one per state, rather than two for the larger states.