Many writers are of the opinion that federal structure of the State is a transitory and temporary stage in the evolution of the unitary State. They cite the fact that almost all federal States are becoming more and more centralized because the central government in them acquires ever more authority and powers. The national government is extending the scope of its powers, while the unit or provincial governments increasingly look to it for financial assistance, planning and regulatory measures. One of the federal States, the German Empire, actually became a unitary State under the Nazi policy of centralisation. There is some truth in this criticism. In modem times, the structure of the federal State is under three strong pressures for centralisation.<\/p>