UPDATE 1-Indonesia's Pertamina plans big jump in capex

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JAKARTA, Nov 12 (Reuters) - Indonesia's state oil and gas firm PT Pertamina plans a 77 percent increase in capital expenditure next year, in order to acquire more oil and gas blocks, finance director Ferederick Siahaan said on Thursday.

Pertamina wants to expand its upstream activities, as it needs to increase oil production following Indonesia's steady slide in overall oil output, and is also looking at several potential gas fields.

"For capex, in 2010, we plan 39 trillion rupiah," or $4.15 billion, Siahaan told reporters, adding that out of this total, Pertamina would use "around 26 trillion rupiah for upstream activities and the rest for other expenditures including downstream."

The company expects to borrow $2.5 billion to help fund the capex, he said. It had said it planned to spend 22 trillion rupiah on capex in 2009.

Siahaan added that 2010 capex was much higher than the planned capex for 2009 because the firm is preparing to buy a stake in Masela block in eastern Indonesia and is planning to increase its investment in the Cepu block in East Java.

The Abadi gas field in Masela block is currently operated by Japan's Inpex (1605.T). Pertamina has said it is seeking a 30 percent participating stake in the project.

Pertamina has a 45 percent stake in the Cepu block, which is set to become one of Indonesia's biggest oil projects with reserves of around 600 million barrels.

Indonesia, which has far more gas than oil, has pushed companies to move faster in developing gas projects as the country badly needs the fuel for domestic industries and exports. ($1 = 9,400 rupiah) (Reporting by Muklis Ali; Writing by Tyagita Silka; Editing by Sara Webb)