China Mobile, the world's largest cellular phone operator, is planning a multibillion-dollar share sale in Shanghai as early as next month to attract domestic investors, sources familiar with the situation said on Monday.

It will likely be the biggest initial public offer of equity ever in China's domestic markets, exceeding Industrial & Commercial Bank of China's 46.6 billion yuan ($6.1 billion) Shanghai IPO last year, the banking sources said.

China Mobile hired KPMG to audit its proposed Shanghai listing late last year. An auditing report has been completed and submitted in a package of listing documents to regulators in Beijing for consideration, said the sources.

"All the necessary documents are well prepared now. The timing of the listing is up to Beijing, but the company definitely aims for as soon as July," said one of the sources.

China Mobile has also hired Goldman Sachs Gaohua Securities to advise on its Shanghai listing, the sources said.

"We don't have a timeframe for an A-share listing. But that's always been the company's intention," a Hong Kong-based China Mobile spokeswoman said.

Hong Kong's Chinese-language Apple Daily newspaper, citing an unnamed mainland Chinese source, said the deal could raise as much as 80 billion yuan. China Mobile shares were up 3.63 percent at HK$78.55 in Hong Kong on Monday afternoon.

Beijing has been encouraging its leading domestic companies to list shares at home, aiming to further develop its capital markets and give local investors more stocks to trade.

Beijing has selected China Mobile as the first of several major Hong Kong-listed Chinese "red chips" that are expected to list in Shanghai by the end of this year, the sources said.

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Top regulators in Beijing have said they were drafting new rules to allow red chips to float shares on mainland bourses.

Three other major red chips, PetroChina, China Telecom and Shenhua Energy, are expected to list in Shanghai before the end of this year, after China Mobile, the sources said.

Beijing is also considering, as part of its long-term economic strategy, establishing a special board within the Shanghai Stock Exchange to attract listings by China-focused overseas companies such as HSBC Holdings Plc. and Bank of East Asia, the sources said.

Officials at the Shanghai bourse declined to comment.

"China Mobile is a pilot and if its listing goes successfully, you will see many others like China Mobile listing domestically," another of the sources said.

The source added that Beijing was expected to speed up its IPO approval process to meet increasing investor demand for shares amid ample market liquidity.

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