Speculation has also swirled about BHP using its strong balance sheet to make other acquisitions, such as in the potash or petroleum sectors, but Citigroup said Rio was the best fit.

必和必拓是否会利用自身财务实力较强的优势进行其他收购，比如在石油等领域，这方面的臆测也不少，不过花旗集团认为还是力拓最合适。

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Michael Yeager, CEO of BHP Billiton Petroleum pointed out at the conference.

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It will apply to firms that mine iron ore, coal and petroleum and affect about 30 of Australia's biggest miners, including BHP Billiton, Rio Tinto and Xstrata.

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