Exhibit 99.1

DATE: Feb. 28, 2012

Apco Reports Net Income for 2011

Declares First-Quarter 2012 Dividend

TULSA, Okla. – Apco Oil and Gas International Inc. (NASDAQ:APAGF) today announced net income attributable to Apco of $31.7 million in 2011, or $1.08 per share, compared with net income of $25.8 million, or $0.88 cents per share in 2010.

The improvement in 2011 net income is primarily due to higher average sales prices, greater equity income from Argentine investment and lower exploration expense compared with 2010. These favorable variances were partially offset by higher non-exploration costs and operating expenses.

Total operating revenues increased by $17 million compared with 2010. Higher average sales prices accounted for $14.3 million of the increase during 2011. A 1 percent sales volume increase – which resulted in 2.5 million barrels of oil equivalent (BOE) for the year applicable to Apco’s consolidated interests – also contributed to higher operating revenues.

Total costs and operating expenses for the year increased by $14.7 million, primarily from higher production costs including depreciation, depletion and amortization expense and taxes other than income.

Higher production costs during 2011 were partially offset by lower exploration expenses. The decrease in exploration expense reflects lower exploration activity including the absence of significant seismic acquisition investments made in Colombia during 2010.

Apco also experienced higher equity income from its 40.72 percent interest in Petrolera Entre Lomas S.A. (Petrolera). For 2011, the benefits of higher average sales prices and greater sales volumes contributed to an increase of $4.3 million in equity income from Argentine investment compared with 2010.

Sales volumes applicable to Apco’s equity interest in Petrolera were 2.2 million BOE in 2011 – an increase of 7 percent.

First-Quarter 2012 Dividend

Apco’s board of directors has approved a regular quarterly dividend of 2 cents per share on the company’s shares. The dividend is payable on April 26, 2012, to shareholders of record at the close of business on April 16, 2012.

2011 and 2012 Capital Program and Operational Update

Capital expenditures attributable to the company’s consolidated interests during 2011 were $35.8 million. Apco’s capital program for 2011 focused on development and exploration drilling in its Neuquén basin properties, including drilling in the Coirón Amargo exploration permit where Apco completed its drilling commitments during 2011 to earn a 45 percent interest in the joint venture.

Exploration activity in the Neuquén basin properties had positive results during the year. Apco tested natural gas in the Lotena formation in development wells that have been placed on production from the Tordillo formation and commenced its investigation of the Vaca Muerta shale in the Coirón Amargo block.

Apco’s primary objectives for 2012 are:

Apco’s 2012 oil and gas capital expenditure budget is $58 million. After taking into consideration the portion of capital expenditures attributable to the company’s equity interest in Petrolera, the combined consolidated and equity capital budget for 2012 is $96 million – the highest level in Apco’s history. In addition, Apco plans to spend approximately$8 million for the acquisition of 3D seismic information.

In December 2011, Apco commenced a three-stage fracture stimulation of a well that was drilled earlier in the year – the CAS x-1. The CAS x-1 well discovered oil in the Tordillo formation, but was placed on production from the Vaca Muerta from which it produced small volumes of oil on an intermittent basis.

After completing the fracture stimulation, the first stage of a long-term production test of the Vaca Muerta commenced on Feb. 8, 2012. During the next 14 days, the well was on intermittent production for 159 hours flowing at an average of 241 barrels per day of 32-33 degree API gravity crude oil through a 2 millimeter choke (approx. 1/12 inch) at flowing pressures of 2,000 psi and above. Over the balance of the testing period, the well was taken off production to enable pressure recovery. Production testing will resume in the near future.

Also during December, Apco commenced drilling the CAS x-4 well in the southeastern portion of the Coirón Amargo exploration permit. This well reached a total depth of 12,149 feet. A core sample of the Vaca Muerta formation has been taken for laboratory analysis. Apco plans to perform a multi-stage fracture of this well after the core analysis is completed and the company has evaluated results of the production test of the CAS x-1 well. In the meantime, completion of the well will proceed in order to test formations underlying Vaca Muerta.

In February 2012, Apco commenced drilling the CAS x-2 well in the central sector of the Coirón Amargo block. The objective of this well is to investigate both the Tordillo and Vaca Muerta formations.

A third multi-stage fracture of an existing well in one of Apco’s producing fields north of Coirón Amargo is preparing to get under way in the near future.

“Our drilling program in the Neuquén basin during 2011 has allowed us to deliver strong results and the ability to grow our business through the drill bit,” said Thomas Bueno, Apco’s president and chief operating officer. “During 2011, we experienced an overall 4 percent year-over-year increase in total sales volumes.

“Our 2012 capital program once again emphasizes development drilling, but provides a strong exploration component that includes start up of exploration drilling in Colombia and continued investigation of the Vaca Muerta shale in the Neuquén basin,” Bueno added.

“Although our test results from the CAS-x-1 to date are encouraging, exploration of the Vaca Muerta in this basin is in the very early stages. At this point, the productive behavior of the formation is not well understood.”

Apco Oil and Gas International Inc.

Summary of Earnings

(In Thousands of Dollars Except Per Share Amounts)

About Apco Oil and Gas International Inc. (NASDAQ: APAGF)

Apco Oil and Gas International Inc. is an international oil and gas exploration and production company with interests in eight oil and gas concessions and two exploration permits in Argentina, and three exploration and production contracts in Colombia. More information is available at www.apcooilandgas.com. Go to http://www.b2i.us/irpass.asp?BzID=1671&to=ea&s=0 to join our e-mail list.

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