Shares in PetroChina Company Limited, China's largest oil and gas producer, opened Monday at 48.6 yuan on their first day of trading in the mainland A share market, up 191 percent from their IPO price of 16.7 yuan.

The price made PetroChina the world's largest listed company by market capitalization. The previous biggest, Exxon Mobil, was valued at US$487.7 billion according to last Friday's share price.

PetroChina raised 66.8 billion yuan (US$8.9 billion) in Shanghai by selling 4 billion A shares, or 2.18 percent of its expanded share capital, in the world's biggest initial public offering (IPO) this year.

Apart from the 4 billion A-shares issued in the public offering, PetroChina's parent, China National Petroleum Corporation (CNPC), holds the rest of the 158 billion A shares, 86.29 percent of the total. It has 21 billion H Shares.

The PetroChina IPO surpassed the 66.58 billion yuan (US$8.88 billion) achieved by China Shenhua Energy Company, the country's largest coal producer, earlier last month.

The offerings of the oil giant have incurred concerns of strained funds and wobbles in the stock market.

China's major stock index dropped 2.31 percent on Nov. 2, also the last trading day before the opening of PetroChina in the mainland A share market.

Chinese shares even slumped nearly 5 percent on Oct. 25, the same day as subscriptions for PetroChina A shares began.

The company is the first of the country's three petrochemical giants including Sinopec and the China National Offshore Oil Corp. (CNOOC) to get listed on overseas stock market.

PetroChina began trading in Hong Kong and its American Depository Receipts were listed on the New York Stock Exchange in 2000. Its Hong Kong share price was 19.60 HK dollars last Friday.

CITIC Securities Co., UBS Securities Co. and China International Capital Corp. are the main underwriters of the issue.

(Xinhua News Agency November 5, 2007)