The Number of Blocks Assigned to Ecopetrol Rises to 10 in Open Round Colombia 2010 / The new block is identified as LLA-6 and covers an area of 76,629 hectares -- ANH publishes final list of assignments

BOGOTA, Colombia, Aug. 12 /PRNewswire-FirstCall/ -- The Colombian National Agency of Hydrocarbons (ANH) has assigned another exploration block to Ecopetrol S.A. ("Ecopetrol" or the "Company") (NYSE: EC; BVC: ECOPETROL; BVL: EC) in the Open Round Colombia 2010 bidding process, following the Company's winning bids for nine other blocks located in various provinces of the country.

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The new block, designated as LLA-6, is located in the provinces of Arauca and Casanare and covers an area of approximately 76,629 hectares. Ecopetrol has offered ANH an investment of US$8 million for exploration activities in this block.

ANH proceeded to assign the block to Ecopetrol, who had come in second in terms of eligibility, after validating the bids and verifying that the requirements of the bidding process's Terms of Reference had been met.

During the Open Round Colombia 2010, which was held in Cartagena on June 22, 2010, Ecopetrol won nine exploration blocks covering an area of approximately 2.8 million hectares. Ecopetrol has a 100% interest in five of these blocks. Ecopetrol's estimated investment in these blocks will be approximately US$102 million over the next three years.

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Ecopetrol is Colombia's largest integrated oil company and is among the top 40 oil companies in the world and the four largest oil companies in Latin America. Besides Colombia, where it accounts for 60% of total production, the Company is involved in exploration and production activities in Brazil, Peru and the United States (Gulf of Mexico). Ecopetrol has the principal refinery in Colombia, most of the network of oil and multiple purpose pipelines in the country, and it is considerably increasing its participation in biofuels.

This release contains forward-looking statements relating to the prospects of the business, estimates for operating and financial results, and those related to growth prospects of Ecopetrol. These are merely projections and, as such, are based exclusively on the expectations of management concerning the future of the business and its continued access to capital to fund the Company's business plan. Such forward-looking statements depend, substantially, on changes in market conditions, government regulations, competitive pressures, the performance of the Colombian economy and the industry, among other factors; therefore, they are subject to change without prior notice.

Contact us for any additional information: Investor Relations Alejandro Giraldo Phone: [phone] Email: [e-mail] Media Relations (Colombia) Mauricio Tellez Phone: [phone] Fax: [phone] Email: [e-mail] Website: http://www.ecopetrol.com.co/

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Ecopetrol S.A.

CONTACT: Ecopetrol Investor Relations: Alejandro Giraldo, [phone],
[e-mail]; or Media Relations (Colombia): Mauricio Tellez,
Phone: [phone], Fax: [phone], [e-mail]

Web Site: http://www.ecopetrol.com.co/