Mining firm Rio Tinto has said claims that employees bribed Chinese steel mill officials were "wholly without foundation" and dismissed reports it had stopped operating in the country.

"Rio Tinto believes that the allegations in recent media reports that employees were involved in bribery of officials at Chinese steel mills are wholly without foundation," iron ore chief executive Sam Walsh said in a statement.

"Rio Tinto continues to operate in China and is maintaining high levels of iron ore shipments from Australia," the statement added.