ExxonMobil and Chevron, the two largest US oil and gas groups, are continuing to lose money on oil and gas production in their home country, in spite of the rise in commodity prices since last year. The losses raise a question over the companies’ forecasts of strong growth in US production, particularly in the Permian basin of Texas and New Mexico. Reporting earnings for the third quarter, Exxon said it lost $238m on oil and gas production in the US, while Chevron lost $26m. The losses were reduced from the equivalent period of 2016, but came as both companies made healthy profits on their international operations. In presentations for analysts on Friday, both companies set out projections showing strong growth in production from US shale resources. Exxon forecast average annual growth of 20 per cent in its shale oil and gas production, with 45 per cent growth in the Permian region. It has been building up its position in the region in recent years, and in September did another deal to acquire more drilling rights, increasing its 6bn barrels of oil equivalent resource base by a further 400m boe. Chevron similarly projected strong growth in production in the Permian Basin, where it has retained a large legacy position built up over decades. John Watson, Chevron’s chief executive who is stepping down at the end of January, said the company was “exceeding expectations” in the Permian. However, unlike “conventional” oil developments, where an initial capital cost to drill wells and install facilities is followed by a long period of production that declines only slowly, shale resources require continual drilling to maintain output.