Endeavour Announces Record Reserve Growth in 2009

HOUSTON, February 16, 2010 - Endeavour International Corporation (NYSE Amex: END) (LSE: ENDV) today
announced a 49 percent increase in proved and probable reserves as of
December 31, 2009 resulting in a record reserve replacement rate of 980
percent of 2009 production, based on 2P reserves.

"This increase is attributable to the success of our North Sea
exploration and appraisal programs and demonstrates our ability to grow the
company through the drill bit," said William L. Transier, chairman, chief
executive officer and president. "We now have four field developments
underway in the United Kingdom. These longer-cycle projects complement our
expanded U.S. onshore initiative that we expect to contribute significantly
to reserve growth in 2010."

Proved and probable reserves at year-end 2009 increased to 38.9 million
barrels of oil equivalent (mmboe) compared to 26.1 mmboe a year ago.
Extensions, discoveries and upward revisions to prior estimates and purchases
added 13.7 mmboe during 2009. Production for the year was 1.4 mmboe.

The upward revisions in 2P reserves were a result of the drilling of two
wells in Cygnus Fault Blocks 2b and 3, the 2007 Bacchus discovery maturing to
development status and better-than-expected performance from several
producing assets.

                      Net Reserves at December 31,
                      ----------------------------
                                                  2009
                                                  ----
    Audited by: Netherland, Sewell
     and Associates, Inc.            Oil       NGL        Gas    Equivalents
                                    (mbbl)    (mbbl)     (mmcf)     (mboe)
                                    ------    ------     ------     ------
    Proved Developed
      Producing                     1,212        26       4,458       1,981
      Non-Producing                   150         -       4,578         913
    Proved Undeveloped              1,973         5      80,064      15,322
                                    -----       ---      ------      ------
      Proved (1P)                   3,335        31      89,100      18,216
    Probable                        7,352        20      79,919      20,692
                                    -----       ---      ------      ------
      Proved + Probable (2P)       10,687        51     169,019      38,908
    Possible                        7,859        34      89,478      22,806
                                    -----       ---      ------      ------
      Proved + Probable +
       Possible (3P)               18,546        85     258,497      61,714

                                                   2008*
                                                   -----
    Prepared by: Netherland,
     Sewell and Associates, Inc.     Oil       NGL        Gas    Equivalents
                                    (mbbl)    (mbbl)     (mmcf)     (mboe)
                                    ------    ------     ------     ------
    Proved Developed
       Producing                      989         -       6,657       2,099
       Non-Producing                  466        19         338         542
    Proved Undeveloped                675         -      20,825       4,146
                                      ---       ---      ------       -----
       Proved (1P)                  2,130        19      27,820       6,787
    Probable                        5,777         7      81,375      19,347
                                    -----       ---      ------      ------
       Proved + Probable (2P)       7,907        26     109,195      26,134
    Possible                       11,034         6     107,090      28,889
                                   ------       ---     -------      ------
       Proved + Probable +
        Possible (3P)              18,941        32     216,285      55,023

*Reserve information has been restated for the disposition of

its Norwegian operations in May 2009 (5.6 mmboe).

Endeavour International Corporation is an international oil and gas
exploration and production company focused on the acquisition, exploration
and development of energy reserves in the North Sea and United States. For
more information, visit www.endeavourcorp.com.

Source: Netherland, Sewell and Associates, Inc

Certain statements in this news release should be regarded as
"forward-looking" statements within the meaning of the securities laws. These
statements speak only of as of the date made. Such statements are subject to
assumptions, risk and uncertainty. Actual results or events may vary
materially.

As of January 1, 2010, the Securities and Exchange Commission (SEC)
changed its rules to permit oil and gas companies, in their filings with the
SEC, to disclose not only proved reserves, but also probable reserves and
possible reserves. Proved oil and gas reserves are those quantities of oil
and gas, which, by analysis of geoscience and engineering data, can be
estimated with reasonable certainty to be economically producible - from a
given date forward, from known reservoirs, and under existing economic
conditions, operating methods, and government regulations - prior to the time
at which contracts providing the right to operate expire. Probable reserves
include those additional reserves that a company believes are as likely as
not to be recovered and possible reserves include those additional reserves
that are less certain to be recovered than probable reserves. We use may use
certain terms in our news releases, such as "reserve potential," that the
SEC's guidelines strictly prohibit us from including in filings with the SEC.
In addition, we do not represent that the probable or possible reserves
described herein meet the recoverability thresholds established by the SEC in
its new definitions. Investors are urged to also consider closely the
disclosure in our filings with the SEC, available from our website at
www.endeavourcorp.com. Endeavour is also subject to the requirements
of the London Stock Exchange and considers the disclosures in this release to
be appropriate and/or required under the guidelines of that exchange.

Investor Relations, Mike Kirksey of Endeavour, +44-(0)-207-451-2364, or +1-713-307-8788; or United Kingdom Broker, Jeffrey Auld of Canaccord Adams, +44-(0)-207-050-6500, for Endeavour; or UK Media, Philip Dennis, +44-(0)-207-743-6363, or Henry Lerwill, +44-(0)-203-178-6242, both of Pelham Public Relations, for Endeavour