The Kuwait Petroleum Corporation (KPC) announced Thursday the Liquefied Natural Gas (LNG) prices - propane and butane - for December.KPC said in a statement that the propane will be sold for USD 770 per metric ton in the current month of December, an increase of USD 20 compared to November price that reached USD 750 per metric ton.The butane will be sold at USD 820 per metric ton during December, with a rise of USD 10 compared to USD 810 per metric ton in November.The prices of propane and butane are affected by hikes and drops of international oil prices.They are also affected by raising and dropping of the US dollar compared to main currencies.The international economy is witnessing a state of fluctuation due to fears in the markets of the future of global economy and possibility of its recovery that affects demand on gas and crude oil.European sovereign debt is considered a major factor in this world economic crisis since it has affected the investors\' trust and pushed them away from engaging in any risky investments in the gas and crude oil.The propane and butane are of multi-purposes, as they are used in cooking, heating and production of petrochemical substances.