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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
The Board of Directors
International Bancshares Corporation:
We consent to the incorporation by reference in the Registration Statement No. 33-15655 on Form S-8 of International Bancshares Corporation of our reports dated March 15, 2006, with respect to the consolidated statements of condition of International Bancshares Corporation and subsidiaries as of December 31, 2005 and 2004, and the related consolidated statements of income, comprehensive income, shareholders' equity, and cash flows for each of the years in the three-year period ended December 31, 2005, management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2005, and the effectiveness of internal control over financial reporting as of December 31, 2005, which reports are incorporated by reference and included in the December 31, 2005 annual report on Form 10-K of International Bancshares Corporation. Our report on the consolidated financial statements refers to a change in the method of accounting for the Company's investment in its statutory business trusts in 2003.
/s/ KPMG LLP
San Antonio, Texas
March 15, 2006
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM