Informed sources revealed that executives from major U.S. oil companies held private meetings with senior officials from OPEC on the sidelines of a conference in Houston to discuss energy affairs, continuing a tradition that started about five years ago when both sides were fierce competitors. Both sides benefit from strong global demand for oil and gas, having achieved record profits over the past year, and the competition between them has diminished with the stabilization of the shale oil boom, which has positioned the United States at the top of global oil producers and reduced OPEC's market share. OPEC once viewed shale oil as a volatile force that undermined its revenues by bringing substantial new oil supplies into the market. Relations have improved after shale oil companies complied with investors' demands to boost capital returns and cut spending on increasing production capacity. A dinner has been held in most recent years during the CERAWeek energy conference in the hub of the American oil industry. This year's dinner is the first attended by Haitham Al Ghais as Secretary General of OPEC, a position he assumed in August.