Khuang Aphaiwong replaced Phibun as prime minister, ostensibly to continue relations with the Japanese, but, in reality, to secretly assist the Free Thai Movement. At the war's end, Phibun was put on trial at Allied insistence on charges of having committed war crimes, mainly that of collaborating with the Axis powers. However, he was acquitted amid intense pressure as public opinion was still favourable to him, as he was thought to have done his best to protect Thai interests. Phibun's alliance with Japan had Thailand take advantage of Japanese support to expand Thai territory into Malaya and Burma.