NuVista Energy Ltd. Announces Filing of its Initial Annual Information Form

May 20, 2004

CALGARY, ALBERTA--(CCNMATTHEWS - MAY 20, 2004) - NuVista Energy 
Ltd. ("NuVista") announces the filing of its Initial Annual 
Information Form ("AIF") for the year ended December 31, 2003 on 
the System for Electronic Document Analysis and Retrieval 
("SEDAR"). The AIF contains additional details about NuVista's 
reserves data and other oil and gas information as mandated by 
National Instrument 51-101, Standards of Disclosure for Oil and 
Gas Activities of the Canadian Securities Administrators. A copy 
of this document may be found on the SEDAR website at 
www.sedar.com.  

NuVista is an independent Canadian oil and natural gas 
exploration, development and production company with its common 
shares trading on the Toronto Stock Exchange under the symbol 
"NVA".  


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NuVista Energy Ltd.
1100, 321 6th Avenue S.W.
Calgary, AB  T2P 3H3
Ph:  (403) 514-7300

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-30-

NuVista Energy Ltd.
Keith A. MacPhail
Chairman
(403) 213-4315

or

NuVista Energy Ltd.
Alex G. Verge
President and Chief Executive Officer
(403) 213-4306

or

NuVista Energy Ltd.
Glenn A. Hamilton
Vice President and Chief Financial Officer
(403) 213-4302
Email: inv_rel@nuvistaenergy.com