The Organization of the Petroleum Exporting Countries (OPEC) agreed on Wednesday to keep the cartel's oil production limit of 30 million barrels per day.

OPEC spokesperson Angela Agoawike said the cartel decided to maintain the output ceiling given the weakness and uncertainty of the world economy in 2013 after the OPEC wrapped up its ministerial meeting.

"Given the demand uncertainties, the conference decided to maintain the current production level of 30 million bpd," Angela noted after the meeting.

She also stressed that "the biggest challenge facing the global oil market in 2013 is uncertainty surrounding the global economy with the fragility of eurozone remaining a major concern."

Besides, the OPEC ministers also voted to reappoint Libyan El-Badri as OPEC Secretary-General for another year. "I enjoy my tenure here in the Secretariat. I try to work my best to serve our member countries." El-Badri said. The OPEC Monthly Basket Price continues to decline in the previous two months, and it once fell below 100 U.S. dollars a barrel in June.

According to its report released Tuesday, the share of OPEC crude oil in global supply continued to drop, accounting for 34 percent of the world's total in November, due to the growth of non-OPEC oil supply.

The OPEC Reference Basket Price is expected to continue declining in next months, given the decrease of Euro zone oil demanding and the increase of the world supply.