Harbour Energy shares slumped on Thursday after the North Sea producer swung to an annual loss.
The stock tumbled more than eleven per cent in early deals as the London-listed company reported losses of $93m (£72.1m), down from a prior year profit of $45m.
North Sea producers have hit out at the UK’s windfall tax, which demands an additional 38 per cent levy on profits from oil and gas.
It was introduced when energy prices soared in the wake of Russia’s invasion of Ukraine in 2022, however, the Labour government on Wednesday outlined plans to bring about its end in 2030.
Harbour Energy said its post-tax loss figure reflected a 108 per cent effective tax rate, up from 93 per cent in 2023.
Wider production at the company increased around 40 per cent year-on-year, driven by its £8.7bn acquisition of Wintershall Dea’s oil-and-gas assets from the German chemicals firm BASF.
It is proposing a final dividend of 13.19 cents per share, up from 13 cents per share the prior year.
“2024 was a transformational year with the completion of the Wintershall Dea transaction, our fourth significant transaction since 2017,” chief executive Linda Z Cook said.
“As a result, we achieved a step change in the scale, resilience and longevity of our business underpinning the potential for material free cash flow generation well into the next decade. At the same time, we delivered another year of solid operational and financial performance.
Cook added: “Looking to 2025, we have had a strong start to the year. We continue to prioritise safe and efficient operations, mature our significant 2C resource base and maintain disciplined capital allocation.
“We remain excited about our future and look forward to realising the potential of our company for all our stakeholders.”