The hostages were released after two days riding an airplane across North Africa, even though Carlos was ordered by his superiors to execute Yamani and his Iranian counterpart Jamshid Amouzegar.
In 1990, Yamani founded the Centre for Global Energy Studies, a market analysis group, and remained involved in private investments and cultural foundations.
[1] His father, Hassan Yamani, was a Qadi in the Hejaz and a respected scholar of Islamic law, acting as Grand Mufti in Indonesia and Malaysia.
[10] Yamani took the lead role in the development of this idea and in 1968 the Organization of Arab Petroleum Exporting Countries (OAPEC) was joined by Saudi Arabia, Kuwait, and Libya.
[17][18] To gain political support, Yamani travelled through Europe, the United States, and Japan with Algerian oil minister Belaid Abdesselam.
[20] Attempts by the United States at bringing together a consumer's cartel failed, and the EEC and Japan called on Israel to withdraw from Arab territories occupied in 1967.
[21][22] On 22 December, the Persian Gulf members of OPEC met again in Tehran where the Shah, backed by the other states, urged that the price of oil be raised to over $20 a barrel.
Fearing a split in OPEC, Yamani decided on a compromise that put oil at $11.65, four times the price of a barrel prior to 16 October.
Saudi Arabia has been criticised for using its dominant position to force its own interests and its long-term production strategy, as a lower price enables the country to keep a high market share and discourages development of alternative energy sources that would curtail the worldwide demand for oil.
The young prince had joined a Kuwaiti delegation, led by oil minister Abdul Mutaleb Kazimi, which Yamani had escorted to the King's office.
[18] On 21 December 1975, Saudi Arabia's Yamani, Iran's Jamshid Amuzegar, and the other OPEC oil ministers were taken hostage at their semi-annual conference in Vienna, Austria.
The attack, which killed three non-ministers, was carried out by a six-person team led by Venezuelan terrorist Carlos the Jackal, which included Gabriele Kröcher-Tiedemann, and Hans-Joachim Klein.
Carlos planned to take over the conference by force and hold for ransom all eleven attending oil ministers, except for Yamani and Amuzegar who were to be executed.
[33] Carlos arranged bus and plane travel for his team and 42 of the original 63 hostages, with stops in Algiers and Tripoli, planning to fly eventually to Baghdad, where Yamani and Amuzegar were to be killed.
[33] Some time after the attack, Carlos's accomplices revealed that the operation was commanded by Wadie Haddad, a founder of the Popular Front for the Liberation of Palestine.
Carlos claimed that Saudi Arabia paid ransom on behalf of Iran, but that the money was "diverted en route and lost by the Revolution".
[33][34] At an OPEC meeting in September 1975 in Vienna, Saudi Arabia continued to oppose sharp increases in the price of oil.
Unable to contact Saudi Arabia from Vienna, Yamani left the meeting and flew to London on his private jet in order to find a secure telephone.
Saudi Arabia and other OPEC members managed to increase production sufficiently to replace that lost from Iran, but this did not prevent panic buying of oil.
In 1984, Saudi Arabia purchased ten Boeing 747s to join the fleet of Saudia Airlines, paid for using 34.5 million barrels (5,490,000 m3) of oil.
Board members have included Edward Heath, Valéry Giscard d'Estaing, and Denis Healey, all of whom were friends of Yamani.