China ranked first globally in terms of the sales of new energy vehicles (NEVs) for a seventh straight year in 2021, despite economic uncertainties and supply-chain pressure, official data showed Wednesday.

The country's NEV sales came in at 3.52 million units last year, according to the Ministry of Industry and Information Technology (MIIT).

"China's NEV sector maintained sound growth momentum in production and sales last year," said Fu Bingfeng, secretary general of the China Association of Automobile Manufacturers, emphasizing the importance of robust NEV sales in underpinning the demand of China's auto market.

China's NEV exports, in particular, posted a strong performance last year, with 310,000 units exported.

The booming sales of NEVs came after the gradual improvement of supporting infrastructure in the country. By the end of 2021, China has built 75,000 charging stations, 2.62 million charging piles, and 1,298 battery replacement stations.

However, China's NEV sector still faces pressure from international competitors and challenges to stabilize its industrial and supply chains, said Guo Shougang, an MIIT official.

Guo urged local authorities to roll out more preferential policies for NEV parking and charging, and to improve policies on car purchase, so as to create a sound environment for boosting NEV sales.

He added that the ministry will step up efforts on building more battery charging facilities in 2022.

Wednesday's data also showed that China's auto output and sales rose 3.4 percent and 3.8 percent in 2021 from a year ago, respectively, ending a streak of three consecutive years of decline.