Russian oil giant Lukoil has declared force majeure at the 400,000-barrels-per-day West Qurna-2 oilfield in Iraq after the U.S. sanctions on Russia’s top oil firms, sources familiar with the matter told Reuters on Monday. Following the October 22 U.S. sanctions on Lukoil and Rosneft, Iraq has stopped all cash and crude payments to Lukoil, according to Reuters’ sources. Last week, reports emerged that Iraq’s state oil marketing company SOMO had canceled three crude loadings from Lukoil this month after the U.S. sanctioned…