China National Offshore Oil Corp (CNOOC; CEO.NYSE, 0883.HK) said that a halt to operations at its Penglai 19-3 oil field following an oil spil in China’s Bohai Bay would reduce its oil output for the year, the Wall Street Journal reported. The firm now expects to produce 40,000 fewer barrels per day, compared with a previous estimate of 22,000 barrels per day. CNOOC shares fell 8.9% in Hong Kong on the news, compared with a benchmark decline of 3%. Analysts expect further full-year output losses, as the oil field is unlikely to resume production soon. “Following the recent downgrade of its 2011 production growth target, a further production loss will likely be viewed negatively,” said Credit Suisse (CS.NYSE, CSGN.SIX) analyst Horace Tse. China’s State Oceanic Administration announced Friday that it had ordered a halt to the company’s Penglai oil field, in the wake of an oil spill by ConocoPhillips (COP.NYSE) in Bohai Bay in June.