NEWSROOM

    VANCOUVER, Aug. 21 /CNW/ - Petro Rubiales Energy Corp. (the "Company" or
"Petro Rubiales") has completed its acquisition of all of the shares of Major
International Oil, S.A. ("Major") originally announced on May 9, 2007.
    Major, now a wholly owned subsidiary of the Company, entered into an
agreement in December 2006 with Pacific Stratus Energy Ltd. ("Pacific
Stratus") under which the parties agreed to combine their efforts to apply for
a Technical Evaluation Agreement ("TEA") over an area of approximately 300,000
hectares in the Arauca Department (the "ARAUCA Area") Llanos Basin, Republic
of Colombia. The ARAUCA Area is located to the south of the Venezuela border
and approximately 60 kilometres east of the Cano Limsn oil field. Under its
agreement with Pacific Stratus, Major has the right to earn up to a 50 percent
interest in any Exploration and Production Contract which results from the
TEA. In order to earn that interest, Major is required to fund the costs
required under the TEA (estimated at US$10.5 million) which includes seismic
re-processing, landsat interpretation of oil and gas anomalies, the
preparation of a tectono-stratigraphic model for the ARAUCA Area as well as
the costs of two exploration wells. Within the ARAUCA Area, the two
exploration wells will test an identified antithetic faulted-block structure
as well as a large, Paleozoic inverted anticline structure. Drilling of the
two exploration wells is planned to commence early next year.
    Commenting on the completed acquisition, Mr. Ronald Pantin, President and
Chief Executive Officer, stated "the acquisition of Major and the resulting
exploration opportunity within the ARAUCA Area demonstrates the Company's
commitment to further growth within the highly prospective, Llanos Basin of
Colombia".
    Petro Rubiales, a Canadian-based company and producer of heavy crude oil,
acquired a 75 percent interest in Rubiales Holdings Limited, owner of 100
percent of Meta Petroleum Limited, a Colombian oil and gas operator which
operates the Rubiales and Piriri oil fields in the Llanos Basin in association
with Ecopetrol S.A. the Colombian, state-owned oil company. The Company is
focused on identifying opportunities primarily within the eastern Llanos Basin
of Colombia.

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    responsibility for the adequacy or accuracy of this news release.