Oil and gas explorer Petroceltic International is to abandon an exploration well off the Bulgarian coast that failed to yield enough gas to justify commercial production.

The Irish firm said its Kamchia-1 exploration well, part of the Galata exploration concession, reached a total depth of 2,887 feet and encountered 56 feet of carbonate sands with sub-commercial gas saturations.

The company said the well has consequently been plugged and abandoned and that the drilling rig was moving on to work on another discovery before being sent to drill Petroceltic’s first exploration wells offshore Romania this summer.

“We are disappointed with the outcome of the Kamchia-1 well and plan to complete the post drill analysis prior to formulating forward plans for the Galata exploration concession,” chief executive Brian O’Cathain said.

Petroceltic’s shares fell 5 per cent in early London trading to 6.33 pence today.