Desite the Japanese surrender to the Allied forces in 1945, the Malay state had become unstable. This was exacerbated by the emergence of nationalism and a popular demand for independence as the British Military Administration took over from 1945 to 1946 to maintain peace and order, before the British began introducing new administrative systems under the Malayan Union. The four neighbouring Malay states held by Thailand throughout the war were returned to the British. This was done under a proposal by the United States, offering Thailand admission to the United Nations (UN) and a substantial American aid package to support its economy after the war. The MPAJA, under the Communist Party of Malaya (CPM), had fought alongside the British against the Japanese, and most of its members received awards at the end of the war. However, party policy become radicalised under the authority of Perak-born Chin Peng, who took over the CPM administration following former leader Lai Teck's disappearance with the party funds.