Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F. 

Form 20-F ___X___ Form 40-F _______

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes _______ No___X____

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Tupi Extended Well Test

Rio de Janeiro, July 6, 2009 – PETRÓLEO BRASILEIRO S/A - PETROBRAS, announces that it has detected a manufacturing issue with the fixation bolts used in the Wet Christmas Tree (a submarine well flow control device) at well 3-RJS-646, which had been performing the Extended Well Test (EWT) in the Tupi Area, in the Santos Basin’s Pre-Salt Cluster, operated by Petrobras (65%) in partnership with BG Group (25%) and Galp-Energia (10%).

A submarine inspection did not detect any oil leak or damage to the equipment. Preventively, pursuant to its Safety, Environment and Health policy, the Company decided to immediately replace the Wet Christmas Tree and Adaptor Base.

The well was closed for the operation to be carried out, and the EWT will be continued after the replacement has been completed.

The results obtained via the EWT thus far, have been in line with the expectations of the Company and will be valuable to define the development plan for the area and, particularly, to provide information about the long-term behavior of the reservoirs in production, about fluid movement and drainage during production, and about submarine outflow.

Petrobras emphasizes that the issue in question is unrelated to aspects concerning field production or the technology and does not have impact in the development of the Santos Basin’s Pre-Salt Cluster.

 

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www.petrobras.com.br/ri/english
Contacts: PETRÓLEO BRASILEIRO S. A. – PETROBRAS
Investor Relations Department I E-mail: petroinvest@petrobras.com.br / acionistas@petrobras.com.br
Av. República do Chile, 65 – 22^nd floor - 20031-912 - Rio de Janeiro, RJ I Tel.: 55 (21) 3224-1510 / 9947

This document may contain forecasts that merely reflect the expectations of the Company’s management. Such terms as “anticipate”, “believe”, “expect”, “forecast”, “intend”, “plan”, “project”, “seek”, “should”, along with similar or analogous expressions, are used to identify such forecasts. These predictions evidently involve risks and uncertainties, whether foreseen or not by the Company. Therefore, the future results of operations may differ from current expectations, and readers must not base their expectations exclusively on the information presented herein.

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This press release may contain forward-looking statements. These statements are statements that are not historical facts, and are based on management's current view and estimates offuture economic circumstances, industry conditions, company performance and financial results. The words "anticipates", "believes", "estimates", "expects", "plans" and similar expressions, as they relate to the company, are intended to identify forward-looking statements. Statements regarding the declaration or payment of dividends, the implementation of principal operating and financing strategies and capital expenditure plans, the direction of future operations and the factors or trends affecting financial condition, liquidity or results of operations are examples of forward-looking statements. Such statements reflect the current views of management and are subject to a number of risks and uncertainties. There is no guarantee that the expected events, trends or results will actually occur. The statements are based on many assumptions and factors, including general economic and market conditions, industry conditions, and operating factors. Any changes in such assumptions or factors could cause actual results to differ materially from current expectations.

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