The National Iranian Oil Company suffered decreased production, because of Iranian inexperience and the AIOC's orders that British technicians not work with them, thus provoking the Abadan Crisis that was aggravated by the Royal Navy's blockading its export markets to pressure Iran to not nationalise its petroleum. The Iranian revenues were greater, because the profits went to Iran's national treasury rather than to private, foreign oil companies. By September 1951, the British had virtually ceased Abadan oil field production, forbidden British export to Iran of key British commodities (including sugar and steel), and had frozen Iran's hard currency accounts in British banks. British Prime Minister Clement Attlee considered seizing the Abadan Oil Refinery by force, but instead settled on an embargo by the Royal Navy, stopping any ship transporting Iranian oil for carrying so-called "stolen property". On his re-election as prime minister, Winston Churchill took an even harder stance against Iran.