Diệm also secretly maintained contact with high-ranking leaders of the Democratic Republic of Vietnam, attempting to convince them to leave Hồ Chí Minh's government and join him. At the same time, he lobbied French colonial officials for a "true independence" for Vietnam, Diệm was disappointed when in June 1948, Bảo Đại signed an agreement to grant Vietnam status as an "associated state" within the French Union, which allowed France to maintain its diplomatic, economic, and military policies in Vietnam. In the meantime, the French had created the State of Vietnam and Diệm refused Bảo Đại's offer to become the Prime Minister. On 16 June 1949, he then published a new manifesto in newspapers proclaiming a third force different from Vietminh and Bảo Đại, but it raised little interest and further, his statement provided evidence to both the French and Việt Minh that Diệm was a dangerous rival. In 1950, the Việt Minh lost patience and sentenced him to death in absentia, and the French refused to protect him. Hồ Chí Minh's cadres tried to assassinate him while he was traveling to visit his elder brother Thục, bishop of the Vĩnh Long diocese in the Mekong Delta. Recognizing his political status, Diệm decided to leave Vietnam in 1950.