Scotland-based oil explorer Cairn Energy said Tuesday its reserve estimate was up modestly because of developments off the coast of Senegal.

Cairn said its estimate of contingent reserves at the SNE field offshore Senegal increased about 20 percent to 385 million barrels of oil, an estimate that doesn't include data still being assessed from regional appraisal wells.

"We are delighted with the results to date of our multi-well evaluation program offshore Senegal, which has confirmed the scale and extent of the significant resource base in this world class asset," Chief Executive Simon Thomson said in a statement.

The Scottish company confirmed a discovery offshore Senegal in January. The company said that, unlike the tough sea conditions in the North Sea or in the Gulf of Mexico, offshore West Africa may be more palatable to energy companies.

Elsewhere, Cairn said it was optimistic about future developments in the British waters of the North Sea, where it raised its working interest in the regional Kraken field to 29.5 percent.

Kraken is one of the few fields slated to ramp up production in a North Sea sector facing pressure from the low price of crude oil. First production from Kraken is expected next year, using a floating production platform.

Field maturation and economic pressures are pushing the North Sea into decline.