The exodus of deep-water drilling rigs from Norway could become a problem for Europe’s most important energy producer as rig demand intensifies in other hotspots around the world, with offshore drilling contractors caught in a tricky spot.

There are currently just 13 active semi-submersible rigs in Norway with all the required certifications, and this is a record low, according to Transocean, the world’s largest deep-water drilling contractor with five active semisubs in Norway.

About 18 months ago, there were up to 22 active semisubs.