By Anandita Mehrotra

(Reuters) -North Sea-focused oil producer EnQuest swung to an after-tax annual profit and declared its first-ever final dividend of $15 million on Thursday, helped by higher oil prices and ongoing debt reduction.

Shares of the London-listed energy group rose 3.4% to 13.8 pence by 0830 GMT as it said it would pay its maiden dividend of 0.616 pence per share in June.

It reported an after-tax profit of $93.8 million for 2024, following a $30.8 million loss the previous year.

EnQuest, which is discussing a possible deal with oil and gas company Serica Energy, declined to give an update on the talks ahead of an April 4 deadline for EnQuest to make an offer.

Serica has previously said the potential deal will be structured as an all-share offer by EnQuest, and will involve a return of capital to existing Serica shareholders, while giving them a majority in the combined company with shares listed in London.

EnQuest's net debt fell to $386 million at the end of last year from $481 million at the end of 2023.

Like other UK oil and gas producers, EnQuest is subject to a windfall tax introduced in response to surging energy prices following Russia's invasion of Ukraine in 2022, which the Labour government increased last October and extended till 2030.

It said earlier this month it planned to overhaul the tax regime after that, but Steve Bowyer, EnQuest's general manager of North Sea operations, said it should be reviewed sooner.

"Consultation is encouraging but we need a change before 2030," Bowyer told Reuters in an interview.

The latest increase in the windfall tax to 38% from 35 took the headline tax rate on the oil and gas sector to 78% - among the highest in the world.

(Reporting by Anandita Mehrotra and Shashwat Awasthi in Bengaluru, Shadia Nasralla in London; Editing by Janane Venkatraman and Tomasz Janowski)