BP is seeking to bolster oil and gas in its portfolio to regain investor confidence and revive underperforming shares.

Amid a pivot back to its fossil fuel roots and away from renewable energy, Britain's BP said it had made its largest oil and gas discovery in 25 years.

BP has made its largest oil and natural gas discovery in 25 years off the coast of Brazil, it said Monday, in a potential big boost for the British company following its strategic shift away from renewable energy to refocus on fossil fuels.