Royal Dutch Shell has filed a criminal complaint against a former executive in its Africa oil exploration business over bribery allegations, which have dogged Shell’s work in oil-rich Nigeria in recent years.

The oil major implicated Peter Robinson in the latest corruption scandal after an internal investigation unearthed suspicions of wrongdoing in the sale of an onshore Nigerian oilfield in 2011.

The Anglo-Dutch group is understood to suspect Mr Robinson of taking kickbacks on the deal to sell Shell’s stake in an aging onshore oil field, known as OML 42, to Nigerian oil firm Neconde Energy.

Its suspicions were piqued after discovering evidence of secret Swiss bank accounts and a Seychelles-registered holding firm in Mr Robinson’s name after a sweep of the executive’s Australian home.

Shell said it was “stunned and disappointed” by what it learned and has filed its criminal complaint with the Dutch authorities.