Felix The chief executive of French oil major Total, Patrick Pouyanne, has dismissed the idea it might buy Irish-founded Tullow Oil, which is its partner in East Africa and Guyana.

Tullow Oil shares plummeted by more than 27% to a 21-year low after the Irish-founded exploration company said production from flagship projects in Ghana has disappointed and that it will reassess the commercial viability of recent discoveries made in South America.