NEWSROOM

/NOT FOR DISTRIBUTION TO UNITED STATES NEWSWIRE SERVICES OR FOR
    DISSEMINATION IN THE UNITED STATES/TORONTO, Aug. 28 /CNW/ - Pacific Rubiales Energy Corp. (TSX: PEG)
announced today that it has closed its offering of $220 million principal
amount of 8% convertible unsecured subordinated debentures, due August 29,
2013 and convertible into common shares of the company at $13.00 per share.
    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., purchased the
convertible debentures. The underwriters also exercised at closing the
over-allotment option to purchase 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 will use the net proceeds of the offering to pay for the
previously announced acquisition of Kappa Energy Holdings Ltd., which is
expected to close in early September 2008. Any excess funds will be used for
the general working capital requirements of the company.

    The securities have not been and will not be registered under the United
States Securities Act of 1933, as amended, or any state securities laws, 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 news release does not constitute an offer to
sell or a solicitation of an offer to sell any of the securities.

    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
22,500 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.

    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