News Releases

September 21, 2006

TSX: “ISR”

Shares Outstanding: 13,250,463

DOMESTIC ACTIVITY UPDATE

International Sovereign Energy Corp. (the “Company”) reports on its Western Canadian operations, as follows;

At Marwayne, Alberta (W.I. 100%) development drilling has been successful. The first two wells (11-C28 and 14-A28) have been drilled, completed and equipped for production with a combined production rate of 100 bbls/day. The Company also drilled one additional well, (5A-28) that is scheduled for completion after a further three wells are drilled on a multi-well pad site. The rig is on site and will commence drilling next week. The Company’s recent drilling has generated additional in-fill drilling opportunities beyond the current four well program. The in-fill drilling opportunities will be pursued in Q1, 2007.

Two wells in the Medicine River area of central Alberta are expected to commence production at 150 BOED, after tie-in is completed during November, 2006.

At Berwyn, Alberta (2-11-82-24W4) (W.I. 100%) completion of the first zone of interest is scheduled for next week. The zones of interest at Berwyn are; Bluesky, Gething, Fahler, Notikewan and Paddy. Tie-in is expected in December, 2006 and production is expected to be at the 160 BOE/D level. In addition, the Company successfully acquired in August, 2006 from the Crown lands sale a prospective land package in the Berwyn Area which provides the Company with additional drill locations. Drilling is scheduled for Q1, 2007.

At Grimshaw, Alberta (10-17) (W.I. 100%) completion is expected pending freeze-up. Additional step-out drilling at Grimshaw is planned for Q1, 2007.

Once the completions and tie-ins of the wells drilled are completed during the balance of 2006 the Company projects a December, 2006 exit rate of 1,000 BOED.

International Sovereign Energy Corp. is an oil and gas exploration development and production company with offices in Vancouver, British Columbia, Calgary, Alberta and Islamabad, Pakistan and is active in the exploration and development of hydrocarbon reserves in Western Canada and internationally.

For further information, please contact:

Omair Choudhry

Chief Financial Officer

Tel: (604) 684-7372

Fax: (604) 684-2407

Or visit our website at www.isove.com

The Toronto Stock Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of this release. Certain information provided in this press release contains forward-looking statements that by their nature are subject to numerous risks and uncertainties and readers are cautioned that actual results may vary considerably from those forecasted.