NORTH Sea-focused Serica Energy has seen its shares surge by around 45 per cent after the firm moved closer to completing an acquisition that got caught in the crossfire between President Trump and Iran.

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Serica agreed in November to buy a 50 per cent stake in the giant Rhum gas field East of Shetland from BP only to find itself facing serious diplomatic complications.

The Iranian oil company owns the other 50% stake in Rhum, which produces the equivalent of around 3% of the UK’s gas output.

Serica and BP applied for a licence from the US Treasury to ensure production from Rhum could continue uninterrupted when the latest sanctions on Iran take effect from next month.

The companies had to extend the deadline for completion of the deal from the middle of this year amid speculation they might have to scrap it.

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But Serica announced yesterday that US authorities have granted a licence to allow production from Rhum to continue, which is valid until 31 October 2019.

The licence will allow US firms to work on the field. Contractors from other countries should not be exposed to secondary sanctions.

Serica said the licence may be renewed on application by the firm.

The award is conditional on Serica ensuring Iran’s share of the revenues generated from Rhum is held in escrow for as long as sanctions apply.

The Iranian Oil Company will not be allowed to exercise any decision-making powers in respect of Rhum during that period.

Serica, which is led by executive chairman Tony Craven Walker, said the granting of the licence by America’s Office of Foreign Assets Control was a significant advance.

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It fulfils a major condition attaching to the deal to buy the stake in Rhum along with interests in the Bruce and Keith fields from BP up to £52m.

“We welcome the constructive approach taken by all parties. This outcome protects a valuable British asset which, together with the Bruce and Keith fields, produces about 5% of UK offshore gas production,” said Serica chief executive Mitch Flegg.

The parties to the deal have agreed to delay its completion again, from the first of November to the end of the month.

Serica said this will allow the arrangements required by OFAC to be put in place and to ensure an orderly, safe and efficient transition.

The company then expects to reap big rewards from what is a bold expansion move.

In August Serica agreed to buy interests in Bruce and Keith from Total for up to $20m, subject to completing the deal with BP.

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Serica thinks the deals will allow it to become a leading UK independent operator. Around 110 staff will transfer from BP to Serica, which is developing an operations centre in Aberdeen.

The company could use the cash generated from its share of production from the three fields to support exploration and development work in the North Sea and other acquisitions.

Serica reckons the deals will help boost activity in the North Sea by putting assets in the hands of a firm that is more likely to invest in them than giants such as BP with their eyes on bigger prizes.

Mr Flegg said: “Serica is now able to move forward to completing the BP and Total transactions, allowing us to focus on optimising the full performance of the Bruce, Keith and Rhum fields, extend production life where possible and ensure maximum economic recovery of remaining reserves to the UK’s benefit.”

Production from Rhum was halted from November 2010 to October 2014 under a previous round of sanctions intended to curb Iran’s nuclear programme.

The field was discovered by BP in 1977, which brought it into production with the Iranian Oil Company in 2005.

Serica lost $8.4m in the first half following a setback on the Erskine field. Revenues fell to $4.6m from $21.9m last time as production from Erskine was suspended following a blockage on the related export pipeline. A new26 kilometre section of line has been laid.

The company hopes to bring the Columbus gas field in the Central North Sea into production in 2021.

Serica shares closed up 33p at 110p, leaving the firm with a stock market capitalisation of £290m.