BP is reviewing its biggest new oil project in the Gulf of Mexico and could delay the £6.6billion scheme.
It said rising costs made the plan for Mad Dog phase 2 difficult to justify.
The company wants to get its core Gulf of Mexico business, which accounts for around a 10th of its global output, back on track after the disastrous 2010 Macondo oil spill, which is still the subjectof a court case in New Orleans.
Construction of Mad Dog 2, which would be BP’s biggest oil development in the Gulf for a decade, was scheduled to start by the end of this year.
BP said the plan was not as attractive as previously modelled, due largely to market conditions and industry inflation, but it fully intended to develop the resources and was “committed to moving forward with the right plan”.
Analyst Jason Gammel said BP would probably push back the final investment decision by about 12 months