Despite the downturn in the energy market, interest remains strong in developing reserves off the Norwegian coast, a petroleum director said.

The Norwegian Petroleum Directorate said 43 companies have submitted applications to develop acreage on the Norwegian continental shelf. With spending suppressed in the weak market, the regulator said sustained interest and stability was a sign of durability.

"The number of applications has been fairly stable in past years, and we see that the [development] scheme is important for maintaining the activity level and realizing the value potential on the shelf," Sissel Eriksen, director of exploration for the NPD, said in a statement.

The Norwegian government said its oil-driven economy has been pressured by lower crude oil prices, with overall investments expected to decline by 12 percent this year.

Statistics Norway, the government's data-recording agency, blamed a decline in petroleum activities for a 4.7 percent decline in total revenue for the second quarter of the year.

Statistics Norway said total investment in the energy sector for 2016 is estimated at $23.6 billion, a 1.4 percent increase from the estimate for 2015.

NPD set a goal of adding 5 billion barrels of oil to national reserves. By 2019, operators expect to start production at the Johan Sverdrup field, the fifth largest discovery ever made on the Norwegian continental shelf.