Menzies continued the expanded immigration program established under Chifley, and took important steps towards dismantling the White Australia Policy. In the early 1950s, external affairs minister Percy Spender helped to establish the Colombo Plan for providing economic aid to underdeveloped nations in Australia's region. Under that scheme many future Asian leaders studied in Australia. In 1958 the government replaced the Immigration Act's arbitrarily applied European language dictation test with an entry permit system, that reflected economic and skills criteria. In 1962, Menzies' Commonwealth Electoral Act provided that all Indigenous Australians should have the right to enrol and vote at federal elections (prior to this, indigenous people in Queensland, Western Australia and some in the Northern Territory had been excluded from voting unless they were ex-servicemen). In 1949 the Liberals appointed Dame Enid Lyons as the first woman to serve in an Australian Cabinet. Menzies remained a staunch supporter of links to the monarchy and British Commonwealth but formalised an alliance with the United States and concluded the Agreement on Commerce between Australia and Japan which was signed in July 1957 and launched post-war trade with Japan, beginning a growth of Australian exports of coal, iron ore and mineral resources that would steadily climb until Japan became Australia's largest trading partner.