Tesla's December sales, which included 245 for export, were almost three times the amount achieved in the same month last year and 34% higher than November's sales.

It also brought Tesla's total sales of China-made cars for last year to at least 473,078, according to Reuters' calculations of CPCA's data, which prior to April did not publish figures for Tesla's China-made car exports.

This accounts for around half of 936,000 vehicles the U.S. automaker delivered globally last year.

Tesla's Shanghai factory, which started delivering vehicles at the end of 2019, makes electric Model 3 sedans and Model Y sport-utility vehicles for domestic and international markets, including Germany and Japan.

The automaker, which has been able to surmount supply chain woes experienced by rivals to post record quarterly deliveries, said during its third-quarter results in October that the Shanghai plant's potential annual output exceeded 450,000 vehicles.

Tu Le, Beijing-based managing director at Sino Auto Insights, said the December numbers showed that the Tesla brand in China remained strong and that it was also operationally "impressive" given that the Shanghai factory had the capacity to make around 42,000 vehicles a month on average.

"They were well over that number in December. And this is despite the chip and battery shortages that other EV makers dealt with."

China's EV market is dominated by domestic brands including BYD (002594.SZ) and Wuling - a local marque that is part of General Motors (GM.N). Tesla is only the foreign brand in the top 10, according to Shanghai-based consultancy Automobility.

The CPCA also said Chinese EV maker Nio Inc (NIO.N) delivered 10,489 cars last month, a year-on-year increase of 49.7%, while Xpeng Inc (9868.HK) delivered 16,000 vehicles. Volkswagen AG (VOWG_p.DE) said it sold more than 13,787 ID. series EVs in China in December, the fourth consecutive month in which the ID. family has delivered more than 10,000 units in China.