Rio Tinto reiterated its offer to buy out Canadian miner Turquoise Hill Resources for $3.3-billion, a day after proxy advisor Institutional Shareholder Services(ISS) recommended voting against the deal.
In a letter addressed to Turquoise Hill shareholders, Rio Tinto said ISS's final conclusion is based on "flawed logic".
Rio agreed last month to buy the 49% Turquoise Hill stake it does not already own for a "best and final" proposal of C$43 per share, after raising its offer twice, as the mining giant sought a 66% stake in Oyu Tolgoi in Mongolia, the world's largest known copper and gold deposits.
ISS on Monday had recommended Turquoise Hill shareholders to vote "against" the deal, joining the Canadian miner's second-largest shareholder, Pentwater Capital Management, in saying "the offer does not represent a suitable value for shareholders".
Turquoise Hill's shares were down 1.5% at C$37.59. 