Brent crude continued to fall as the US market opened on Monday, deepening losses for the fourth day and hit a 2-week low due to fears over a slowdown in demand for fuel and increasing supply, which could lead to a market surplus once more.
Brent crude fell 1.4% to the lowest since November 5 at $80.80 a barrel, after opening at $81.94, and hit a high at $82.46.
Brent fell 0.7% on Friday, the third straight daily loss, after the US drilling rigs count rose.
Oil prices lost around 0.5% last week, the third straight weekly loss, due to the US dollar's rally against a basket of major currencies.
OPEC lowered in its monthly report its global demand forecast during the fourth quarter of this year by 330,000 barrels per day from last month's forecast.
OPEC referred the rise in energy prices as the reason behind this slowdown in the global economic recovery, which renewed fears about the decline in global demand for fuel.
This came amid growing speculation that the US administration will resort to tapping the strategic oil reserve to calm prices, amid news that the White House is discussing a plan to ease the rise in inflation by tapping the strategic reserve or stopping exports.