Later in 1953 a covert mission to remove Mohammed Mossadegh from power was instigated by Britain's Churchill government and the U.S. Eisenhower administration. Mossadegh had become Iran's democratically elected prime minister and he had nationalised oil possessions of the British-owned Anglo-Iranian Oil Company (now British Petroleum) after Britain had refused to negotiate away its single most valuable foreign asset. Robin Zaehner had developed contacts in Iran and when the British were expelled, Woodhouse took his contacts to the CIA station chief. Thus a conspiracy to overthrow Mossadegh was staged in a joint mission between the CIA and MI6. The CIA named the operation Operation TPAjax, erroneously referred to as Operation Ajax, TP standing for the Soviet-backed communist Tudeh Party of Iran. MI6 activities were codenamed "Operation Boot".