The weekly average crude oil price of the Organization of Petroleum Exporting Countries (OPEC) hit 52.28 U.S. dollars per barrel, a 1.86-dollar jump on the previous week, the cartel's secretariat said on Monday.

Freezing cold winter weather in the United States continued to drive the demand for heating fuel last week.

And the colder-than-normal temperatures in U.S. markets were expected to linger until Feb. 18.

According to the latest report from the U.S. Department of Energy, the U.S. distillate stocks, including diesel and heating oil, have fallen in the previous weeks to well below what market analysts had expected.

Moreover, the planned slash of OPEC oil output by 500,000 barrels per day (bpd) took effect on Feb.1, which also helped boost the price of crude oil last week.

And Saudi Arabia, the world's largest oil producer, had already informed the customers of its impending 158,000-bpd cut, according to a report from the Wall Street Journal.

In the meantime, the heightened geopolitical risks, especially the threat of a planned strike from the two main Nigerian oil workers' unions, also helped push the oil prices higher.

The Nigerian oil workers' unions decided to press for stepped-up security, as dozens of local oil workers, Nigerian soldiers and several foreigners have been killed in the volatile Niger Delta region in recent years.