One of Britain’s leading renewable energy engineers has threatened to sue the Government claiming a pioneering tidal power project he patented was handed to Rolls-Royce.

Rupert Armstrong-Evans claims the move was politically motivated to raise the Government’s profile and he felt he had been “stabbed in the back” after working for 18 months on the Severn Tidal Reef Project.

The scheme was for a giant tidal reef to be built in the Severn estuary that would generate power and allow shipping to pass.

A DECC spokesman said the allegation was “groundless nonsense” and the Rolls-Royce plans were different.