Ford’s electric Mustang Mach-E was the best-selling vehicle in Norway in May, the first full month of registrations for the crossover.

Battery-electric vehicles made up 60.4 percent of all new cars sold in Norway last month, said the Norwegian Road Federation (OFV), up from 43.1 percent a year ago, as the country seeks to become the first to end the sale of cars with petrol and diesel engines by 2025.

By exempting fully electric vehicles from taxes imposed on internal combustion engines, Norway has turned its car market into a testing ground for automakers seeking a path to a future without fossil fuels.

A total of 1384 electric Ford Mustang Mach-E crossovers were registered in May for a 10 percent share of Norway's overall car market, ahead of Toyota's RAV4 hybrid crossover and Skoda's electric Enyaq crossover. The Tesla Model 3 sedan took sixth place.

"Our realistic goal is to remain prominent in the sales statistics for several months to come," Ford's Norway CEO, Per Gunnar Berg, said in a statement.