LONDON, April 10, 2014 /PRNewswire/ -- Platts – Oil production from the Organization of the Petroleum Exporting Countries (OPEC) plunged 550,000 b/d from February to 29.56 million b/d in March -- its lowest level since mid-2011 -- according to the latest Platts survey of OPEC and oil industry officials and analysts. The decline followed February production of 30.11 million b/d and was mainly attributable to insurgent attacks which shut a key export pipeline in Iraq, and a renewed downward swing in Libyan production. Saudi Arabia also reduced output because of lower refining demand due to maintenance. The survey showed Saudi output at 9.6 million b/d, down from 9.7 million b/d in February and the lowest level since June last year, when the kingdom's output was estimated at 9.65 million b/d. Together, Saudi Arabia, Iraq and Libya accounted for 440,000 b/d of the overall drop. "The Iraqi reduction is viewed as particularly unsettling," said John Kingston, Platts global director of news. "It comes just a month after a huge jump in output that followed improvements to the country's exporting capabilities in the south. Given that the often-troubled northern pipeline continues to get hit by difficulties, I suspect the Iraqi monthly number will continue to be volatile." Iraqi output fell by 200,000 b/d to 3.15 million b/d. The Iraq- Turkey pipeline, which carries Kirkuk crude from Iraq's northern fields to Turkish Mediterranean port Ceyhan, remained out of action more than a month after the early March attacks on the line that forced some northern production to be curtailed. Iraqi oil minister Abdul Karim Luaibi said Wednesday that the pipeline could become operational in about a week.