TGS-NOPEC (OSL:TGS) TGS UPDATE ON CLAIM FOR DAMAGES FILED WITH ARBITRATION PANEL

TGS-NOPEC (OSL:TGS) Asker, 22. September, 2008. In preparation for the upcoming arbitration hearings with Wavefield, TGS has elected to narrow its claim for damages from $460 - $830 million as previously presented to the arbitration court to $488 - $510 million. The claim is duly substantiated by detailed calculations presented to the Arbitration Panel. Consequently, TGS has lowered the upper limit for its claim to $550 million, down from the $700 million originally presented in the writ.

Arbitration hearings are scheduled to commence on November 3 to 13, 2008 and conclude by January 5 to 9, 2009. TGS remains confident about the arbitration process and looks forward to concluding the matter.

For more information, contact:

Arne Helland Chief Financial Officer Tel: +47 66 76 99 31/+47 91 88 78 29 Email: arne.helland@tgsnopec.no

TGS-NOPEC

http://www.tgsnopec.no/

ISIN: NO0003078800

Stock Identifier: XOSL.TGS

US: Other OTC: TGSNF.PK