A labourer works at a pump jack in PetroChina's Daqing oil field in China's north-eastern Heilongjiang province November 4. - Reuters

PetroChina became the world's first company worth more than US$1 trillion on Monday, surging past Exxon Mobil as the Chinese oil producer's shares nearly tripled in their first day of trading in China.

State-owned PetroChina Company, a unit of state-owned China National Petroleum Corp, is the country's biggest oil and gas producer.

Its Shanghai initial public offering of four billion shares raised US$8.94 billion - a record for a mainland bourse.

Adding the value of PetroChina shares traded in Shanghai, Hong Kong and New York - and those still owned by the government - the company's total market capitalisation ballooned to just over US$1 trillion, compared to Exxon Mobil Corp's US$488 billion.

Outstanding shares

However, more than 85 per cent of the shares outstanding - 157.9 billion shares - are held by PetroChina's parent company CNPC and are unlikely to trade in the market any time soon.

PetroChina's new shares listed in Shanghai surged to 43.96 yuan (US$5.90) Monday, nearly triple the IPO price of 16.70 yuan (US$2.24).

The stellar performance was expected. Shares in elite companies like PetroChina tend to soar in their trading debuts given the strong appetite among Chinese investors for highly valued companies.

Like other yuan-denominated 'A shares' traded in China, the PetroChina shares issued in Shanghai are meant for domestic investors and are not generally available to foreign buyers.

They account for 2.18 per cent of the company's enlarged share capital of 183.02 billion shares.

"PetroChina's return to the A-share market is a result of the Chinese economy's fast growth and surging energy demand," the company said in a statement. "PetroChina's public offering will bring renewed energy to domestic capital markets, and also provide an important investment indicator."

Before PetroChina's IPO, coal producer China Shenhua Energy Company's debut in Shanghai in September was the largest for a domestic exchange, raising US$8.91 billion.

The benchmark Shanghai Composite index has more than doubled in value this year as investors have piled into the market chasing a slew of IPOs by big-name companies, hoping for higher returns than they can earn on bank savings.

The index fell 2.5 per cent Monday, or 143.36 points, to 5,634.45 as institutional investors cut holdings in energy and financial companies to buy into PetroChina.

As of Friday, PetroChina's market value was US$456.6 billion.

That was based on the company's share price in Hong Kong, where it has listed 21.09 billion shares, or about 11.5 per cent of total stock. Those shares closed Monday at HK$18, or US$2.31.

In Shanghai, PetroChina's shares closed Monday at a much higher US$5.90, lifting the value of company's remaining 162 billion shares - mostly held by CNPC - to US$955 billion.

Shares value

Jiemin

Adding the value of PetroChina's Hong Kong shares, worth about US$49 billion, the company's total market capitalisation rose to more than US$1 trillion.

PetroChina's status as the world's most highly valued company by market capitalisation thus does not necessarily reflect stronger profitability or productivity than its rivals.

The company has seen revenues soar amid surging oil prices, but has struggled to boost production from its aging domestic oil fields.

In refining, it has struggled with a widening gap between soaring world crude oil prices and state-controlled prices for oil products in the domestic market.

PetroChina reported that its first-half net profit rose 1.4 per cent from a year earlier on modest output growth, to 81.8 billion yuan (US$10.8 billion), compared with 80.7 billion yuan a year earlier.

Like other Chinese energy giants, PetroChina is investing heavily in both overseas and domestic oil and gas fields as it rushes to meet soaring demand. The company said it plans to use around 37.8 billion yuan (US$5 billion) of the proceeds from the Shanghai IPO to help finance five projects aimed at boosting its crude oil output and refining capacity.

Its lustre appears to have been undimmed by Berkshire Hathaway Inc's decision to sell off all its 2.3 billion PetroChina shares.

The company made about US$3.5 billion on the sale of that US$488 million investment, Berkshire Hathaway Chairman and Chief Executive Warren Buffett has said in interviews.

- AP