BHP Billiton continues its campaign against the planned resources tax by saying that its implementation would impact dividends to 540,000 shareholders.

BHP BIlliton chief executive Marius Kloppers reiterated his earlier pronouncements that the super-profits tax would threaten Australia's competitiveness and would affect BHP's future investment strategies.

Kloppers warned BHP major projects may move offshore if the proposed tax measure went ahead. He said the Bowen Basin coal project in Queensland could be one of the projects moving offshore when the planned super tax is implemented.

BHP Billiton had earlier said it will hold shareholders meeting across the nation to explain the mining company's position on the proposed super-tax.

In a letter to shareholder, BHP chairman Jac Nasser said the shareholders meeting will discuss what impact the 40 per cent tax would have on the company's operations in Australia.

Since the planned super-profits tax have been announced, global mining firms including BHP Billiton, Xstrata, and Rio Tinto have publicly expressed their opposition and warned to step up campaign against it.

The planned super-profits tax, if implemented, would raise the effective corporate tax rate on super profits made from non-renewable mining resources to 40 per cent from July 2012, scrapping about $9 billion from the industry. Mining executives said such amount of tax would definitely affect the operations and cash flow of their companies.