CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the use of our report dated February 29, 2008 with respect to the consolidated financial
statements of Augusta Resource Corporation as at and for the year ended December 31, 2007 included in this
Registration Statement on Form 40-F, filed with the U.S. Securities and Exchange Commission.
/s/ Ernst & Young LLP
Vancouver, British Columbia, Canada
February 29, 2008