Personal diplomacy was Holt's strong point – he believed diplomatic ties could be strengthened by making intimate connections with other world leaders. This approach was disliked by his external affairs minister, Paul Hasluck, who in his memoirs accused him of believing in "instant diplomacy" and crediting his personal charms for advances made by diplomatic officials. As prime minister, Holt's first overseas trip was to South-East Asia in April 1966, where he visited Malaysia, Singapore, South Vietnam, and Thailand. He toured Cambodia, Laos, South Korea, and Taiwan in March and April 1967, and had planned to visit Burma, India, Indonesia, Japan, and Pakistan in 1968. Most of those countries had never before been visited by an Australian prime minister. There were also a number of reciprocal visits from East Asian leaders, including Eisaku Satō of Japan, Souvanna Phouma of Laos, and Thanom Kittikachorn of Thailand. The most controversial of those occurred in January 1967, when Prime Minister Nguyễn Cao Kỳ of South Vietnam visited on Holt's personal invitation – issued without consulting cabinet. Public sentiment was beginning to turn against the war, and Ky's visit was met with large demonstrations; opposition leader Arthur Calwell issued a statement calling him a "miserable little butcher". Ky nonetheless handled himself well, and "The Bulletin" called his visit a "personal triumph".