THE chief executive of Shell said the North Sea was still important for the oil and gas giant, which could invest in the province for decades to come.

Peter Voser reiterated Shell’s concerns that the controversial Budget tax hike could make some small developments unviable.

However, he said the company would still go ahead with big investments in the kind of bumper projects that could generate the returns it targets.

Asked where the North Sea fit with Shell’s strategy, Mr Voser said: “It’s an important area for us still.

“Because of the new tax we see smaller and more mature (projects) being challenged on the profitability point of view but we see the two bigger projects going ahead, and they are multibillion projects.”

Mr Voser was referring to the BP-operated Clair and Schiehallion developments off Shetland, in which Shell is a partner.

A host of oil and gas firms have warned that the 12 percentage point increase in the rate of tax applied to North Sea profits could hit investment in the area.

Small fields and older developments are seen as especially vulnerable.

Mr Voser was speaking in a conference call with journalists who were visiting the $19 billion (£11.6bn) Pearl Gas to Liquids development in Qatar.

This is a vast plant in the desert where Shell has built a complex facility in which it can turn gas produced offshore Qatar into high value liquids. These include diesel fuel and base oils that can be used to produce lubricants.

This is typical of the kind of mega-projects on which Shell wants to focus investment.

Mr Voser noted Shell had a raft of big schemes in development or planning around the world. He highlighted the potential in areas such as Australia.

Shell has been in talks with Rosneft of Russia about possible collaboration on Arctic exploration in Russia, where BP’s attempts to conclude a similar deal with the state-owned firm foundered.

However, asked by The Herald whether the company could continue to invest in the North Sea for as long as decades to come, Mr Voser said: “I think it could be decades, yes.”

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