Anadarko to Acquire Kerr-McGee Corporation & Western Gas Resources, Inc. in Separate Transactions Totaling $23.3 Billion

Business Wire, June 23, 2006

HOUSTON -- Anadarko Petroleum Corporation (NYSE: APC):

--Deals Create Leading Positions in Two of North America's Most Prolific Producing Regions

--Portfolio to Be Optimized Through Asset Sales

Anadarko Petroleum Corporation (NYSE: APC) today announced it has agreed to acquire Kerr-McGee Corporation (NYSE: KMG) and Western Gas Resources, Inc. (NYSE: WGR) in separate all-cash transactions totaling $21.1 billion, plus the assumption of debt estimated at $2.2 billion.

"We are creating a combined company with industry-leading positions in the deepwater Gulf of Mexico and the Rockies, two of the fastest-growing oil and natural gas producing regions in North America," Anadarko Chairman, President and CEO Jim Hackett said. "The core assets being acquired strongly complement Anadarko's existing properties, providing the scale and focus needed to deliver more robust, predictable and efficient growth. Kerr-McGee's outstanding deepwater holdings and skill sets will elevate Anadarko into the top echelon of deepwater operators. Similarly, Kerr-McGee's long-lived natural gas resource plays in Colorado and Utah, along with Western Gas Resources' in Wyoming, will combine with Anadarko's assets to make us one of the largest producers in several of the most prolific basins in the Rockies. Together, these acquisitions create a more focused portfolio, which will enhance our ability to deliver very competitive growth rates and returns."

Hackett emphasized that the transactions are consistent with Anadarko's strategy, which is built around the company's core competencies in unconventional resource development and high-impact exploration.

"Two years ago, we unveiled a strategy that included a solid North American foundation of onshore resource plays, a growing deepwater Gulf of Mexico program and an expanding international portfolio," he said. "Kerr-McGee and Western Gas Resources strengthen Anadarko's position on all three counts, with captured growth projects that are consistent with our core skill sets. The transactions enable us to create a more focused operating strategy with a larger and lower-risk asset base."

Hackett said Anadarko will conduct a thorough review of the consolidated assets to select divestiture candidates, with the dual goals of paring acquisition-related debt and refocusing the portfolio.

"All three companies have certain assets that we will likely deem to be non-core once combined," he said. "Even with divestitures that we believe could generate substantial after-tax proceeds, we expect the proposed acquisitions to be accretive to both earnings and cash flow on a pro forma basis."

Anadarko will finance the acquisitions through a $24 billion, 364-day committed acquisition facility provided by UBS, Credit Suisse and Citigroup. Anadarko plans to use proceeds from asset sales, free cash flow from operations and the issuance of equity to reduce debt over the next 18 to 24 months.

"Given our outlook for energy markets, these transactions make a lot of sense for Anadarko shareholders. We expect to hedge up to 75 percent of the acquired production through late 2008 using a series of three-way collars, with floors designed to ensure a return on our investment and ceilings that allow considerable upside," Hackett said. "We also expect cost reductions as we consolidate certain administrative functions, but the biggest synergies are expected to come from combining the complementary assets of the three companies and the skills of their employees. In today's tight labor markets, gaining qualified people is a bigger focus than achieving cost savings through consolidation.

"Anadarko is offering Kerr-McGee and Western's shareholders significant premiums over the companies' recent current stock prices, but looking backward 30 days results in premiums that are more comparable to precedent transactions. In any case, we believe we are capturing a substantial disconnect between current property valuations and equity market valuations, and gaining some exceptional properties and talent in the process," Hackett said. "The day-one metrics on proved reserves and daily production are in-line with other recent transactions. On a full-cycle basis, including the acquisition and future development costs, we expect to ultimately recover 3.8 billion barrels of oil equivalent (BOE) from the acquired properties at less than $12.00 per BOE. Opportunities to gain access to such large, high-margin resource opportunities at such economic full-cycle costs are rare, and we are excited about the value we expect to create for Anadarko shareholders."

SUMMARY OF THE KERR-MCGEE CORPORATION TRANSACTION

Anadarko has agreed to acquire Kerr-McGee Corporation in an all-cash transaction totaling $16.4 billion, or $70.50 per Kerr-McGee share, plus the assumption of net debt and other liabilities estimated at $1.6 billion.

Kerr-McGee's year-end 2005 proved reserves (excluding pending Gulf of Mexico shelf divestitures) totaled 898 million BOE, of which approximately 62 percent is natural gas. Proven undeveloped reserves represented 30 percent of the total. Production in 2006 is expected to be about 92 million BOE, with natural gas representing approximately 60 percent of the total. Anadarko expects to ultimately recover more than 3.1 billion BOE on the Kerr-McGee properties, at a full-cycle cost of approximately $39.2 billion ($12.40 per BOE), including the acquisition cost.