NEWSROOM

Pacific Rubiales Files Reviewed 2008 First Quarter Results
May 21, 2008

    TORONTO, May 21 /CNW/ - Pacific Rubiales Energy Corp. (TSX: PEG) today
announced that it has filed amended results for the three month period ending
March 31, 2008. The financial statements have been amended to reflect the fact
that the statements have now been reviewed by the Corporation's auditors; no
changes to any of the interim consolidated financial statements resulted from
the review, except for the correction of two transposed lines in note 6(b).
    Complete reviewed interim financial statements and MD&A are available on
the Company's website or on SEDAR at www.sedar.com.

    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. Further information is available
on our website at www.pacificrubiales.com

    This press release contains forward-looking statements based on
assumptions, uncertainties and management's best estimates of future events.
Actual results may differ materially from those currently anticipated.
Investors are cautioned that such forward-looking statements involve risks and
uncertainties. Important factors that could cause actual results to differ
materially from those expressed or implied by such forward looking statements
are detailed from time to time in the Company's periodic reports filed with
the British Columbia Securities Commission and other regulatory authorities.
The Company has no intention or obligation to update or revise any
forward-looking statements, whether as a result of new information, future
events or otherwise.

    %SEDAR: 00007953E



For further information:
For further information: Carlos Perez, Chief Financial Officer, (416)
362-7735, cperez@pacificrubiales.com