UPDATE 1-Shell Nigerian onshore oil output heavily down

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LONDON Oct 13 (Reuters) - Royal Dutch Shell's (RDSa.L: Quote) onshore oil output in Nigeria has been heavily curtailed by violence, the company's chief executive said on Tuesday.

"We have a huge proportion of our onshore production shut in at this stage," Peter Voser told reporters. "I think we are now at 120,000 barrels per day and we used to be close to 300,000. These are Shell's share (production)."

Like other major oil firms in Nigeria, Shell operates in the West African in joint venture with the state oil company.

Violence in the Niger Delta, where Shell has long been a dominant player, has declined since President Umaru Yar'Adua offered an unconditional pardon to militants in June. Activists say peace will only last if work can be found fast for those who have disarmed. [ID:nL5719632]

Voser said it was to early to say whether the improvement could be sustained.

"The overall security situation is still very fragile, the government had some success with their amnesty programme and we are looking now towards the next few weeks to see how this influences the whole security situation," Voser said.

"But it would be by far too early to say that it has improved. We are still dealing with the same kind of issues." (Reporting by Daniel Fineren; writing by James Jukwey)