NEWSROOM

/NOT FOR DISTRIBUTION TO UNITED STATES NEWSWIRE SERVICES OR FOR
    DISSEMINATION IN THE UNITED STATES/TORONTO, Aug. 7 /CNW/ - Pacific Rubiales Energy Corp. (TSX: PEG)
announced today that, in connection with the proposed public offering of
convertible debentures previously announced on August 6, 2008, it has entered
into an agreement with a syndicate of underwriters led by GMP Securities L.P.,
and including Canaccord Capital Corporation, Cormark Securities Inc.,
Macquarie Capital Markets Canada Ltd. and Thomas Weisel Partners Canada Inc.,
to issue $220 million principal amount of 8% convertible unsecured debentures.
The debentures will expire five years and one day from the date of issuance
and will be convertible into common shares of the company at $13.00 per share.
    The company has granted to the underwriters an option, exercisable in
whole or in part for a period of 30 days following the closing of the
issuance, to purchase up to an additional $20 million principal amount of
debentures at the same offering price, to cover over-allotments, if any, and
for market stabilization purposes.
    Pacific Rubiales plans to use the net proceeds of the offering to pay for
the previously announced acquisition of Kappa Energy Holdings Ltd. Any excess
funds will be used for the general working capital requirements of the
company.
    A preliminary short-form prospectus for the issuance was previously filed
with all provinces of Canada, other than Quebec. A (final) short-form
prospectus is expected to be filed with each of the securities commissions as
soon as possible. The offering is scheduled to close on or about August 28,
2008 and is subject to certain conditions including, but not limited to, the
receipt of all necessary approvals including the approval of the Toronto Stock
Exchange and the securities commissions.
    The securities offered have not been registered under the United States
Securities Act of 1933, as amended, and may not be offered or sold in the
United States or to, or for the account or benefit of, U.S. persons absent
registration or an applicable exemption from registration requirements. This
release does not constitute an offer for sale of securities in the United
States.

    Pacific Rubiales, a Canadian-based company and producer of natural gas
and heavy crude oil, owns 100 percent of Meta Petroleum Limited, a Colombian
oil operator which operates the Rubiales and Piriri oil fields in the Llanos
Basin in association with Ecopetrol S.A. the Colombian, national oil company.
The Company is focused on identifying opportunities primarily within the
eastern Llanos Basin of Colombia as well as in other areas in Colombia and
northern Peru. Pacific Rubiales has a current net production of approximately
21,000 barrels of oil equivalent per day, with working interests in the
Rubiales, Piriri and Quifa concessions and the Caguan, Dindal, Rio Seco,
Puli B, La Creciente, Moriche, Guama, Arauca, Tacacho and Jagueyes blocks in
Colombia and blocks 135, 137 and 138 in Peru.

    This news release contains certain "forward-looking statements" and
"forward-looking information" under applicable Canadian securities laws
concerning the business, operations and financial performance and condition of
Pacific Rubiales Energy Corp. Forward-looking statements and forward-looking
information include, but are not limited to, statements with respect to
estimated production and reserve life of the various oil and gas projects of
Pacific Rubiales; the estimation of oil and gas reserves; the realization of
oil and gas reserve estimates; the timing and amount of estimated future
production; costs of production; success of exploration activities; and
currency exchange rate fluctuations. Except for statements of historical fact
relating to the companies, certain information contained herein constitutes
forward-looking statements. Forward-looking statements are frequently
characterized by words such as "plan," "expect," "project," "intend,"
"believe," "anticipate", "estimate" and other similar words, or statements
that certain events or conditions "may" or "will" occur. Forward-looking
statements are based on the opinions and estimates of management at the date
the statements are made, and are based on a number of assumptions and subject
to a variety of risks and uncertainties and other factors that could cause
actual events or results to differ materially from those projected in the
forward-looking statements. Many of these assumptions are based on factors and
events that are not within the control of Pacific Rubiales and there is no
assurance they will prove to be correct. Factors that could cause actual
results to vary materially from results anticipated by such forward-looking
statements include changes in market conditions, risks relating to
international operations, fluctuating oil and gas prices and currency exchange
rates, changes in project parameters, the possibility of project cost overruns
or unanticipated costs and expenses, labour disputes and other risks of the
oil and gas industry, failure of plant, equipment or processes to operate as
anticipated, the business of Petro Rubiales and Pacific Stratus not being
integrated successfully or such integration proving more difficult, time
consuming or costly than expected as well as those risk factors discussed or
referred to in the annual Management's Discussion and Analysis and Annual
Information Form for Pacific Rubiales filed with the securities regulatory
authorities in all provinces of Canada and available at www.sedar.com.
Although Pacific Rubiales has attempted to identify important factors that
could cause actual actions, events or results to differ materially from those
described in forward-looking statements, there may be other factors that cause
actions, events or results not to be anticipated, estimated or intended. There
can be no assurance that forward-looking statements will prove to be accurate,
as actual results and future events could differ materially from those
anticipated in such statements. Pacific Rubiales undertakes no obligation to
update forward-looking statements if circumstances or management's estimates
or opinions should change except as required by applicable securities laws.
The reader is cautioned not to place undue reliance on forward-looking
statements. Statements concerning oil and gas reserve estimates may also be
deemed to constitute forward-looking statements to the extent they involve
estimates of the oil and gas that will be encountered if the property is
developed.
    Boe may be misleading, particularly if used in isolation. A boe
conversion ratio of 6 mcf: 1 bbl is based on an energy equivalency conversion
method primarily applicable at the burner tip and does not represent a value
equivalency at the wellhead.

    %SEDAR: 00007953E