ATP Sells Stake in Gulf of Mexico Producing Assets

ATP Oil & Gas has entered into an agreement to sell 25% of its working interest in seven Gulf of Mexico developments which consist of ten offshore blocks for $19.5 million. Based on the December 31, 2003 reserve report prepared by Ryder Scott Company, L.P., ATP sold 10.56 Bcfe of proved reserves in the GOM which were 93.5% proved undeveloped.

ATP received $10.5 million in February of 2004 and will receive the remaining $9.0 million in April of 2004. The proceeds from the sale were used to reduce debt and this sale has improved ATP's overall liquidity. As operator, ATP and its new partner will drill development wells on all seven developments over the next two years.

ATP recently reported its proved reserves as of December 31, 2003, were 303 Bcfe of which 202 Bcfe are in the GOM and 101 Bcfe are in the North Sea.

At December 31, 2003, ATP owned an interest in 50 offshore blocks in the GOM and 12 offshore blocks in the North Sea. The sale of 10.56 Bcfe of proved reserves was effective as of January 1, 2004, and will reduce ATP's GOM reserves by 5.2% and total company worldwide reserves by 3.5%.

T. Paul Bulmahn, Chairman & President of ATP, stated, "We are pleased to add a quality partner who can participate in the development of projects in ATP's Gulf of Mexico portfolio."