Sales in the commercial vehicle sector rebounded even higher. In May, sales totaled 520,000, up 48 percent year-on-year as workers are returned to their offices.

Total sales in the first five months reached 1.85 million, down 1 percent year-on-year.

Yet the new energy vehicle sector is yet to turn positive. A total of 84,000 units were sold in May, still a 25.8 percent fall from the same month in 2019. Sales from January to May were 295,000, a 40 percent nosedive year-on-year.

Warren Buffett-backed BYD sold 11,325 vehicles in May, only half of the figure of the same month last year.

But some carmakers are having more success. Tesla was the top-selling electric car brand with 11,095 vehicles.

The US company began deliveries from its massive new Shanghai factory around the start of the year. Monthly registrations of new Tesla vehicles in China have fluctuated this year amid the virus, from a low of 2,314 in February to a high of 12,710 in March, according to data from China Automotive Information Net.

Chinese electric car startup Nio delivered 3,436 vehicles last month, representing a 216 percent growth year-on-year. Its total deliveries this year totaled 10,429.

After growing rapidly for several years, electric car sales have lost momentum since the government moved to limit subsidies in mid-2019.

The pandemic also hurt demand and falling oil prices have made gasoline vehicles more competitive.

The government still considers electric cars a priority and has added a slew of fresh stimulus measures to help the industry recover.

UBS said the pandemic will produce little long-term impact on the sector.

"It may have affected some carmakers' financing," said UBS auto analyst Paul Gong. "But long-term goals, like China's goal of electric cars accounting for 25 percent of the country's total sales by 2025, are immune to the pandemic."

China's vehicle exports remained at a lower level as well. Statistics from the China Association of Automobile Manufacturers showed that merely 49,000 vehicles were sold in May, down 37.4 percent year-on-year.

From January to May, vehicle exports totaled 323,000, falling 17.5 percent year-on-year.

Chen said the fall in exports was primarily because of the waning demand overseas because of the pandemic.

"The demand is yet to recover in overseas markets, and export-oriented companies are not safe now," Chen said.

He estimated that vehicle exports will drop by 200,000 units this year, from about 1 million in 2019, as the coronavirus erodes global demand.