Aberdeen-based Faroe Petroleum said the results from the Rodriguez well in the Norwegian Sea confirmed it has found potentially valuable gas condensate.
The initial results suggest the find could contain as much as 126 mil-lion barrels recoverable oil equivalent.
With a 30% stake in the Wintershall-operated licence, Faroe would be entitled to up to 38 mboe of a find on that scale.
The find was made in the secondary area targeted by the well.
Earlier this month, Faroe announced the well found no sign of oil or gas in the primary target area.
The result may help to vindicate Faroe's faith in the exploration potential of Norway, where it has amassed the biggest licence position of any UK independent.
Rodriguez was drilled eight kilometres from the Maria find that Faroe made in 2010.
Chief executive Graham Stewart said: "This significant discovery gives the partnership a good indication of further upside potential on the rest of the licence block."
Faroe, which has interests off the eponymous islands and in the UK, expects to drill five exploration wells in 2013, all in Norway.
Separately, Enegi Oil said it has agreed to farm out part of a block east of Shetland in a deal that highlights overseas interest in the UK North Sea.
Enegi will farm out a 50% stake in the exploration area of block 3-23 to Azimuth, backed by Seacrest Capital, a Bermuda-based energy investment group.
It said Azimuth agreed to undertake all the relevant work to assess the hydrocarbon potential of the exploration area within the first 12 months of signing the agreement.
Enegi and ABT will retain a 100% working interest in the Malvolio Area of the block.