SHARES in North Sea-focused Serica Energy have plunged 12 per cent after President Trump’s decision to take the US out of the nuclear deal with Iran caused a complication for the firm.

London-based Serica has agreed to buy a stake in an East of Shetland gas field, Rhum, which is 50 per cent owned by the state-owned Iranian Oil Company.

However, describing the nuclear deal as defective on Tuesday, Mr Trump said he would be reinstating the highest level of sanctions on Iran and warned other countries not to help its government.

Brent crude jumped around $2 per barrel yesterday, to $77.10/bbl, amid expectations exports from Iran will be cut.

Noting the statements made by Mr Trump, Serica said: “ The Company is evaluating the implications of these statements and how they relate to the Rhum field.”

It added: “We will update the market, as appropriate, in due course.”

Led by executive chairman Tony Craven Walker, Serica agreed to acquire a 50 per cent interest in Rhum from BP along with stakes in two other producing fields in November for up to £52 million, in what it described as a transformational deal. Serica has one producing field currently. The deal is due to complete in the third quarter.

Production from Rhum was suspended in 2010 after Europe imposed sanctions on Iran.

It restarted in 2014 after the UK Government agreed to hold revenues due to Iran while sanctions remained in place. The sanctions were lifted in 2016.

BP won a licence from the US authorities in that year to continue operations on the field.

Shares in Aim-listed Serica closed down 9.6p at 71p.