"The pieces are coming together, " said Tom Botts, Royal Dutch Shell's head of European exploration and production, when asked when the field would start pumping gas. Botts was speaking at a Deutsche Bank oil and gas conference in London on Thursday.

A local Shell E&P Ireland spokesman refused to comment on Botts' remarks. It was company policy, the spokesman said, not to comment on when production would begin.

Botts said the company is winning support for the Corrib project as it tries to agree an alternative pipeline route. "Over the last year we've been able to improve and increase support for the project, " Botts said. "We're all aware of the challenges we have had with Corrib."

Shell has cleared 350,000 tons of peat from the site of an onshore terminal and is now in full construction mode, Botts said.

Discovered in 1996, the Corrib field contains about 1.1 trillion cubic feet of natural gas. It would supply 60% of Ireland's expected needs for the fuel in the next two decades and help reduce the country's reliance on imported fuels. Ireland imports around 80% of its gas.