SHARES in Bowleven have fallen four per cent following an update on a long-awaited drilling campaign by the oil and gas firm, which moved its headquarters from Edinburgh to London last year following a boardroom cull.

The Aim market-listed firm released the initial results of an appraisal programme completed off Cameroon, which included the first wells it had drilled in the country’s waters since 2013.

Bowleven hopes to establish that finds made on its acreage off Cameroon are commercially viable.

When drilling started in May Bowleven’s chief executive Eli Chahin said the programme aimed to further improve the already robust economics for future development of what he described as a world class asset.

Bowleven said yesterday the results of the IM-6 well indicated the find it appraised could contain up to 250 billion cubic feet more gas than had been thought.

The second well discovered oil. Bowleven will work with partners on the licence, Jersey-based New Age and Russia’s Lukoil, to assess the significance of the find.

Bowleven said it is is re-assessing development options for the Etinde field with its partners.

Up to $40m of Bowleven’s costs on the IM-6 and IE-4 wells were due to be carried by New Age and Lukoil under a $250m stake sale negotiated with the firms by former chief executive Kevin Hart in 2014.

Mr Hart and four other directors were voted off the board in March last year following a campaign for change led by the Crown Ocean Capital investment firm founded by German financiers Christian Petersmann and Konstantin Stoyanov.

Bowleven retains a 25% stake in Etinde, which is operated by New Age.

The chief executive of New Age, David Stoopin, said of the $55m drilling programme yesterday: “We are pleased with the successful performance of the 2018 appraisal campaign and the results confirming additional resources in the Etinde permit.”

He added: “we now look forward to the next steps in optimising the development solution on the Block, prior to a development Final Investment Decision.”

Shares in Bowleven closed down 1.1p at 26.1p.

They closed at 33.25p on the day Mr Hart lost his place on the board.

Bowleven shed around 30 jobs in the wake of the boardroom upheaval.

Mr Chahin curbed exploration activity to focus on Etinde.