NEWSROOM

    TORONTO, May 15 /CNW/ - Pacific Rubiales Energy Corp. (TSX: PEG) today
announced the results for the three month period ending March 31, 2008. All
amounts are expressed in U.S. dollars. The first quarter results reflect the
impact of the acquisition of Pacific Stratus Energy Ltd. on January 23, 2008
as well as the 1:6 common share consolidation on May 9, 2008.
    First quarter 2008 was a period of significant achievements for Pacific
Rubiales. Total gross crude oil production was 31,302 barrels per day. Gas
production averaged 37 million cubic feet during this period (6,555 barrels of
oil equivalents), for a total a daily production of 37,857 barrels of oil
equivalents. This operational level was achieved with a competitive operating
cost of $5.08 per barrel of oil equivalents. In terms of net production, crude
oil averaged 12,016 barrels per day. Including gas production, the total
Company production was 18,571 barrels of oil equivalents.
    Pacific Rubiales continued developing its ambitious business plan which
contemplates an increase of heavy crude oil production to 126,000 barrels per
day by the end of 2009. Capital expenditures related to this plan totaled
$81.8 million to the end of first quarter, including a committed equity share
amount of $40.5 million related to construction of 260 kilometre pipeline to
be in operation by the fourth quarter of 2009. Capital expenditures in the
quarter were $41.3 million and included $14 million for exploration and
production costs for the La Creciente block, $10.9 million for the appraisal
well program to enhance the static model of the Rubiales field, $6.5 million
for the construction of an additional central processing facility at the
Rubiales field and $4.8 million for seismic programs.
    On March 3, 2008, the Company announced new reserves for the Rubiales
heavy crude oil field effective December 31, 2007, which estimated gross
proven and probable reserves to be 270.7 million barrels of heavy oil (net
proven and probable reserves 96.7 million barrels), representing an increase
of 47.5% over the amounts reported in the May 31, 2007 reserve report. The
gross proven reserves have been estimated at 137.7 million barrels (net
50.2 million barrels), up 462% from May 31, 2007. Gross proved plus probable
plus possible reserves were estimated to be 315.4 million barrels of heavy
oil.
    Net sales reported for the quarter were $94.9 million, an increase of 76%
over previous quarter due to higher production, the acquisition of Pacific
Stratus, increasing oil and gas prices and higher volume sold in the
international market related to the Company's successful new commercial
scheme. EBITDA (earnings before income taxes, depreciation and stock
compensation) was strong as a result of high sales combined with competitive
level of costs allowed Pacific Rubiales to reach an EBITDA of $39.4 million. A
new commercial scheme allowed the exporting of 191,824 barrels at an average
price of $83.48, yielding a substantially higher net back than domestic sales.
From April 2008 Pacific Rubiales will be able to export its total production
which is expected to result in an increase in sales and EBITDA. At the end of
third quarter a total volume of 176,658 barrels, with a total market value of
$16 million, has been accumulated as inventory for export during April 2008.
    EBITDA was more than offset by a $41 million non-cash and unrealized
foreign exchange loss and a $31 million non-cash charge upon the granting of
stock options in the quarter, resulting in a net loss of $53.2 million or
$0.30 per share. The foreign exchange loss was a result of the effect of the
appreciation of the Colombian Peso in the first quarter on future income tax
liabilities following the acquisitions of Pacific Stratus and Rubiales
Holdings Ltd. Cash flow from operations before non cash working capital was
$38.0 million.
    Total assets were $1.8 billion, shareholders' equity was $1.3 billion and
the Company has $137 million in cash as at March 31, 2008.
    Ronald Pantin the Company's CEO commented, "We are pleased with the
financial results and are just beginning to see our Company's cash generating
potential from operations. We are on track for our goal of 126,000 barrels per
day by the end of 2009."
    Complete 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