Total's Chief Executive Patrick Pouyanne is taking a "prudent" approach to oil prices after 2019 when bottlenecks in U.S. oil infrastructure could be resolved, he told an oil conference in Stavanger, Norway, on Monday. There are more than a dozen U.S. energy pipelines on the drawing board, some of which are still seeking financing. The projects would pave the way for greater U.S. oil and gas exports and relieve a bottleneck in West Texas shale fields that is.