Prime Minister Churchill asked President Eisenhower for help in overthrowing Mossadeq. The anti-Mossadeq plan was orchestrated under the code-name 'Operation Ajax' by CIA, and 'Operation Boot' by SIS (MI6). The CIA and the British helped stage a coup in August 1953, the 1953 Iranian coup d'état, which established pro-Western general Fazlollah Zahedi as the new PM, and greatly strengthened the political power of Shah Mohammad Reza Pahlavi.