China will implement a new vehicle tax law starting Jan 1 next year, according to a statement posted to the State Administration of Taxation website Dec 18.

The new law will omit or reduce taxes on vehicles using alternative energy, the statement said.

BYD Co, the Chinese carmaker partly owned by Warren Buffett’s Berkshire Hathaway Inc, rose by the most in a month on Dec 19 in Shanghai after the government said a new vehicle tax may not apply to autos using alternative energy.

BYD, maker of the E6 electric car, gained 6 percent to 22.73 yuan at 2:48 pm local time.