Shares of BYD Co Ltd, the Chinese carmaker backed by Warren Buffett, rose about 1.28 percent in Shenzhen on Thursday, in a lukewarm reaction to its chairman Wang Chuanfu's move to increase his stakes in the company.

On Wednesday, BYD said that Wang, the company's chairman and CEO, had bought 1 million of BYD's Hong Kong-listed shares on the previous day, and may increase his shareholding further in the future.

It was BYD's latest move to stabilize the company's share price. BYD's Hong Kong shares fell 29 percent on December 18 in record trading, logging their biggest one-day drop, in an unexplained slide that wiped out around $1.2 billion of its market capitalization.

BYD's Shenzhen-traded shares were up 1.28 percent, closing at 37.15 yuan ($5.99) Thursday. Its Hong Kong-listed shares are not trading as the Hong Kong bourse is closed on Christmas Day.

"Wang's share purchase only represents his own confidence in the company, and will not change its future performance," said Zhang Jing, an analyst at Phillip Capital.

This year, BYD is suffering badly from sluggish sales of its gasoline cars and weak exports, she said.

Big shareholders of China's top four State-owned banks and domestic steel makers such as Baoshan Iron & Steel Co Ltd have all announced share purchase plans in the past amid sluggish trading in the companies' shares, but had mixed results.