(Adds comment from President Widodo and analyst)
By Wilda Asmarini
JAKARTA, Aug 2 (Reuters) - Indonesia's state-owned energy company, Pertamina, expects production from the Rokan oil block to reduce its crude oil import needs by around one-quarter, said Daniel Syahputra Purba, Pertamina Senior Vice President for Strategic Growth.
"Right now we import around 400,000 (barrels per day), and the reduction of 100,000 bpd is pretty significant," Purba told reporters at an industry conference on Thursday, referring to the addition of crude from Rokan from 2021.
Pertamina will in 2021 take over operatorship of the Rokan block, Indonesia's second-largest crude producing oilfield, from its current operator Chevron.
Besides reducing Indonesia's imports, Indonesian President Joko Widodo said on his official Facebook page on Thursday the transition will increase Pertamina's contribution to national oil and gas output to 60 percent in 2021, from 36 percent now.
"This block, covering 6,220 (square) kilometers, has 96 oilfields. Three of the fields have very good oil production potential, namely Duri, Minas and Bekasap," Widodo said.
Earlier this week, however, Pertamina Upstream Director Syamsu Alam said Rokan output had "declined continuously" from 2007 to 2015.
"How much (Rokan) produces in 2021 will depend on how much it's producing prior to the handover," he said. Alam added that he hoped Pertamina could control the decline in Rokan's output or increase it.
The change in operatorship is anticipated to also result in a reduction in Indonesia's crude exports, as more crude from Rokan would be used in domestic refineries.
Sushant Gupta, research director at energy consultancy Wood Mackenzie, told Reuters that crude oil exports from Rokan's Duri and Minas fields average around 60,000 to 80,000 barrels per day, largely to Japan for use in power generation and to China for small-scale refineries.
"Replacement for Indonesia's export reductions could come from the rising U.S. exports to Asia, (and) increased production from Russia and OPEC countries in the next few years will also fill the void left by Indonesia's declining exports," he said.
Output by Chevron's local unit Chevron Pacific Indonesia, operator of the Rokan block, hit 207,148 barrels per day (bpd) in the first half of 2018, below a 2018 target of 213,551 bpd.
Widodo, who sharply rebuked Pertamina in May for not spending enough on exploration, is currently reviewing candidates for a new chief executive for the company.
"We've proposed at least three names of candidates to the president," Deputy State Owned Enterprise Minister Fajar Harry Sampurno told reporters on Thursday.
Sampurno said it was important a new chief executive was named soon because important long-term decisions were waiting to be made.
Pertamina's previous CEO was sacked in April after repeated clashes with the government over retail fuel price controls that were estimated to have cost the company $1.4 billion from January to September last year.
Nicke Widyawati, who previously served as Pertamina's human resources director, has been serving as acting CEO since then. (Reporting by Wilda Asmarini in JAKARTA; Additional reporting by Jessica Jaganathan in SINGAPORE; Writing by Fergus Jensen; Editing by Christian Schmollinger and Tom Hogue)