UPDATE 1-Gazprom to explore Vietnam's offshore fields

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MOSCOW, May 23 (Reuters) - Russian state-controlled gas export monopoly Gazprom (GAZP.MM) said on Friday it has signed an agreement with Vietnam's state oil monopoly Petrovietnam to explore four new offshore blocks.

Gazprom said in a statement that joint company VietGazprom, which has been exploring a Vietnamese offshore deposit since 2000, will operate the new fields.

Gazprom also said the two firms would create a separate joint venture, GazpromViet, to take part in oil and gas projects in Russia and third countries.

Russian state oil firm Zarubezhneft, a pioneer in communist Vietnam's oil industry, will represent Gazprom in the new venture, said the statement. Zarubezhneft and Petrovietnam are already long-time partners in their equal joint venture Vietsovpetro, which produces around 8 million tonnes per year (160,700 barrels per day) on offshore fields in Vietnam.

The two companies said earlier this month that they were creating a new consortium to develop 13 new oil deposits in Russia's West Siberian Nenets region, where they plan to produce up to 130,000 bpd in 10 years. (Reporting by Tanya Mosolova)