State-run Mexican company Pemex is gearing up to drill a new deep-water well less than three miles (4.8 kilometres) from the US maritime border, its latest exploration push in the Perdido foldbelt that, if successful, could test an international framework for managing transboundary resources.

The Tiaras-1 probe could be spudded as soon as 18 November using the Seadrill semi-submersible West Pegasus, according to explor­ation plans approved by the country’s oil regulator the National Hydrocarbons Commission.

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