1 March 2007

Gran Tierra Secures $50 Million Credit Facility With Standard Bank PLC

CALGARY, ALBERTA, MARCH 1, 2007, Gran Tierra Energy Inc. (OTCBB: GTRE) today announced that the Company has secured a three-year senior revolving credit facility of up to US$50 million with Standard Bank Plc. Proceeds from the facility will be used for Gran Tierra’s petroleum operations in South America.

The initial borrowing base under the facility is $7 million and amounts drawn down under the facility bear interest at the Eurodollar rate plus 4%. The facility is secured primarily on the Company’s Colombian assets. Additional terms of the credit facility agreement will be included in the Company’s 8-K to be filed with the Securities and Exchange Commission.

Dana Coffield, President and Chief Executive Officer of Gran Tierra, stated , “In keeping with our mission to grow our base of production and cash flow from development and exploration opportunities, this credit facility provides further resources for expanding the Company’s current drilling program and future exploration activities in South America.”

About Gran Tierra Energy Inc.
Gran Tierra Energy, Inc. is an international oil and gas exploration and production company, headquartered in Calgary, Canada, incorporated and traded in the United States and operating in South America. The Company holds interests in producing and prospective properties in Argentina, Colombia and Peru. To date, the Company has pursued a strategy that focuses on establishing a portfolio of producing properties, development and exploration opportunities, through selective acquisitions, to provide a base for future growth. Additional information concerning Gran Tierra is available at www.grantierra.com. Investor inquiries may be directed to info@grantierra.com or 1-800-916-GTRE (4873).

Forward Looking Statements
This press release contains ‘forward-looking statements’ within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, including without limitation those statements regarding the Company’s ability to exploit oil and gas exploration opportunities. These statements are expressed in good faith and based upon a reasonable basis when made, but there can be no assurance that these expectations will be achieved or accomplished. Although the forward-looking statements in this release reflect the good faith judgment of management, forward-looking statements are inherently subject to known and unknown risks and uncertainties that may cause actual results to be materially different from those discussed in these forward-looking statements including, but not limited to, our ability to adequately or effectively deploy funds available from our new credit facility to potential business opportunities or to positively impact the results of the Company’s operations. Readers are urged not to place undue reliance on these forward-looking statements, which speak only as of the date of this release. We assume no obligation to update any forward-looking statements in order to reflect any event or circumstance that may arise after the date of this release, other than as may be required by applicable law or regulation. Readers are urged to carefully review and consider the various disclosures made by us in the our reports filed with the Securities and Exchange Commission, including those risks set forth in the Company’s Annual Report on Form 10-KSB filed on March 10, 2006, as amended, which attempt to advise interested parties of the risks and factors that may affect our business, financial condition, results of operation and cash flows. If one or more of these risks or uncertainties materialize, or if the underlying assumptions prove incorrect, our actual results may vary materially from those expected or projected. We undertake no obligation to update these forward looking statements.