On February 19, 1965, some units of the Army of the Republic of Vietnam commanded by General Lâm Văn Phát and Colonel Phạm Ngọc Thảo launched a coup against General Nguyễn Khánh, the head of South Vietnam's ruling military junta. Their aim was to install General Trần Thiện Khiêm, a Khánh rival who had been sent to Washington D.C. as Ambassador to the United States to prevent him from seizing power. The attempted coup reached a stalemate, and although the trio did not take power, a group of officers led by General Nguyễn Chánh Thi and Air Marshal Nguyễn Cao Kỳ, and hostile to both the plot and to Khánh himself, were able to force a leadership change and take control themselves with the support of American officials, who had lost confidence in Khánh.