Aker BP has discovered an oil and gas reservoir while drilling near its Alvheim Field in the North Sea, the Norwegian firm said on Feb. 4.

Known as Froskelaar (Frog's Leg) Main, the reservoir is estimated to hold between 45 million and 153 million barrels of oil equivalents, and may straddle Norway's maritime border with Britain, the company added.

"The drilling operation will continue, and a comprehensive data collection program will be performed to determine the size and quality of the discovery," Aker BP said in a statement.

When reserves are found to stretch across the British-Norwegian offshore border, the two nations share the revenue from production based on estimates of how much oil and gas is located on each side.

Aker BP is operator of the license with a 60% stake, while Sweden's Lundin Petroleum and Eni's Vaar Energi each hold 20%.

Aker BP is 40 %owned by Norway's Aker ASA and 30% by BP Plc.