May 1 About 1.36 million barrels per day of Nigerian production is shut-in due to militant attacks, sabotage and workers' strike. This represents more than 40 percent of the West African country's installed output capacity of around 3 million bpd. The stoppage halted virtually all Exxon's 800,000 barrels per day of production in Nigeria and forced the company on Monday to declare force majeure on its shipments, meaning it could not fulfill contractual obligations to clients. (Reuters)

May 6 The NYMEX near-month WTI contract rose to over $120 per barrel for the first time, settling at $121.84 per barrel. (Reuters)

May 7 Exxon Mobil has lifted a force majeure on its crude oil exports from Nigeria, traders said today. (Reuters)

May 19 President Bush signed into law a bill that temporarily halts adding oil to the Strategic Petroleum Reserve, the measure Congress passed in an effort to lower gasoline prices. The legislation forbids adding to the stockpile until crude prices drop below $75 a barrel. (Reuters)

May 21 The NYMEX near-month WTI contract rose to over $130 per barrel for the first time, settling at $133.17 per gallon. (Reuters)

May 23 Mexico's oil exports fell sharply in April and production also slipped, putting pressure on the government to overhaul energy laws as the country's biggest oil field declines. Oil output fell in April to 2.77 million barrels per day, remaining below the firm's 3.0 million bpd target for the seventh straight month. Mexico is the world's No. 6 producer of oil by volume and the No. 10 exporter, according to the EIA. (EIA, Reuters)

May 27 Senior officials from five Arctic countries, Canada, Denmark, Norway, Russia and the United States, met in Greenland to discuss sovereignty over the Arctic Ocean, which could hold up to one-quarter of the world's undiscovered oil reserves. (Reuters)

May 28 Indonesia quits the Organization of the Petroleum Exporting Countries according to its Energy Minister. The country's crude oil output has fallen in recent years due to ageing wells, a lack of investment, and the absence of any major oil finds. Its status as a net importer means it would benefit from lower oil prices, putting it at odds with other OPEC members. (Reuters)