VIENNA, May 13 (Xinhua) -- The weekly average oil prices of the Organization of Petroleum Exporting Countries (OPEC) surpassed 115 U.S.dollars and set a new weekly record of 115.69 U.S. dollars per barrel (dpb), the Vienna-based cartel said Tuesday.

    These prices were 7.32 U.S. dollars higher than those last week and surpassed the previous record of 110.13 dpb set at the end of April.

    The prices jumped to 111.60 dpb Monday and kept rising in the following five consecutive trading days, hitting 119.13 dpb Friday.

    Oil analysts predicted that the prices would go higher and reach 150 dpb over the coming six months.

    Uncertainty over the future oil supply of OPEC, economic recession in the United States as well as the large amount of speculation on the oil market remain the main boosters of high prices.

    OPEC member country Nigeria's output fell to the lowest level in a decade last month, falling by 164,000 barrels to 1.88 million barrels a day due to the rebel attacks on Royal Dutch Shell pipelines.

    Oil study body Platts also released relative data, pointing out that OPEC offered 350,000 barrels less a day in April. Its director John Kingston explained that the sharp drop of the Nigerian output showed how a member country can influence its total output.

    However, the oil cartel insisted that the current high prices could not reflect the fundamental market and blamed the weak dollar and other factors outside OPEC's control for the price rise.

    OPEC's General Secretary Abdalla Salem El-Badri said Thursday in a statement that some member countries could hardly find a buyer for their spare output.

    The daily prices of OPEC set Monday a new historic high of 119.71 dpb, approaching 120 U.S. dollars. The prices have risen for eight consecutive trading days since May 1.