In the course of their pursuit of economic independence, Fianna Fáil also provoked what is known as the Anglo-Irish Trade War with Britain in 1933, by refusing to continue paying back "land annuities" money provided under the Land Purchase (Ireland) Act 1903 by the British Government to enable Irish farmers purchase their own land. The British in retaliation raised tariffs on Irish agricultural produces, hurting Ireland's export trade. De Valera in turn raised taxes on the importation of British goods. The burden of this standoff fell on the cattle farmers, who could no longer sell their cattle at competitive rates in Britain. Additionally the Fianna Fáil government continued to collect half the land annuities as taxation. Police and sometimes troops were used to seize cattle off farmers who would not or could not pay. Farmers aggrieved at these policies were one of the principal support bases of the Blueshirt movement