Harbour Energy has revealed it expects to pay another £800million in tax in 2024 as it continues to be battered by the Energy Profits Levy.
The London-listed firm - the North Sea's biggest operator - has been hit hard by the windfall tax, which has disproportionally affected the operators of mature assets in the UKCS.
Around 94% of Harbour's production is in the North Sea currently, but the firm is looking at international diversification in response to the fiscal uncertainty facing the UK oil and gas sector.
In a trading update ahead of the firm's AGM this morning, Chief Executive Linda Cook was upbeat about the firm's future as it moves towards completing the acquisition of Wintershall Dea next month.
The deal has has now cleared two major regulatory hurdles, receiving clearance from the Federal Ministry of Economics and Climate Action in Germany, as well as Norway's Ministry of Energy.
Ms Cook said: "During the first quarter, we continued to deliver safe and responsible operations, maximise the value of our UK production base and advance our organic growth projects.
"At the same time, we made significant progress towards completion of the Wintershall Dea acquisition which will transform our portfolio and capital structure and support enhanced and sustainable shareholder returns."
In better news for Harbour shareholders, Ms Cook said the firm's net debt was now just £80million ($100million) and the firm's reserve-based lending (RBL) facility remains undrawn.