PTR.L Regulatory News (PTR)

PetroNeft Resources plc ('PetroNeft' or 'the Company')

Operations Update - Completion of Drilling of S-375 well

PetroNeft (AIM: PTR) an oil & gas exploration and production company operating in the Tomsk Oblast, Russian Federation, and 50% owner and operator of Licences 61 and 67 is pleased to provide an update on the S-375 delineation well at Sibkrayevskoye oil field.

Highlights

· S 375 delineation well and S-375s sidetrack well contain 4.8 m and 14.8 m respectively of net oil pay based on log and core data

· Testing contractor being mobilised to field with results expected by end September

· Reserve calculation and Development Plan being updated

Drilling of the S-375 delineation well has been successfully completed. The objective of the well was to determine the sand distribution and confirm the oil water contact at the southern edge of the field. The well was drilled as a deviated well from the Pad 2 surface position to a targeted location 1.5 km to the south. The wireline logs indicate there is about 4.8 m of net oil pay in the well with the top of the Jurassic J1 interval located at -2,346 m tvdss, which was on prognosis, and the oil-down-to confirmed at -2,357 m tvdss.

The well was then sidetracked (S-375s) from the surface casing to a location about 400 m north of the Pad 2 surface position. The log and core evaluation of the primary Jurassic J1 reservoir indicates there is about 14.8 m of net oil pay and the top of the J1 interval is located at -2,334 m tvdss which is about 3 m high to prognosis. The net pay is thicker than encountered at other wells drilled at the northern part of Sibkrayevskoye, which typically had about 10 m of net oil pay.

The S-375s well has now been cased and cemented and we would expect the perforation and testing of the well to be completed by the end of September. Assuming a successful test, the current plan is to produce the well on pump this winter season along with the S-373 well with the oil being trucked to the Lineynoye central processing facility by winter road.

The reserve estimate and Development Plan for the field is being updated with the S-375 and S-375s drilling results in conjunction with our joint venture partner Oil India.

A map of the location of the S-375s well is included on the Company website, www.petroneft.com.

Dennis Francis, Chief Executive Officer of PetroNeft Resources plc, commented:

"We are pleased with the results of the S-375s well which confirms that Sibkrayevskoye is a large oil field with better than forecast net pay thickness and quality near the Pad 2 location, which looks likely to be brought into production in the coming months. This strong outcome is tempered by the outcome at the initial target well, which will limit the southern extent of the field somewhat. We look forward to sharing the results of the well test and reserve update with the shareholders when available."

For further information, contact:

The information contained in this announcement has been reviewed and verified by Mr. Dennis Francis, Director and Chief Executive Officer of PetroNeft, for the purposes of the Guidance Note for Mining and Oil & Gas Companies issued by the London Stock Exchange in June 2009. Mr. Francis holds a B.S. Degree in Geophysical Engineering and a M.S. Degree in Geology from the Colorado School of Mines. He has also graduated from the Harvard University Program for Management Development. He is a member of the American Association of Petroleum Geologists and the Society of Exploration Geophysicists. He has over 40 years' experience in oil and gas exploration and development.

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