A new survey of the international oil industry has provided the clearest picture to date of the impact that the Chancellor's North Sea tax raid has had on the perception of the UK Continental shelf as a place to invest.

The survey will be seen as a rebuke to Deputy Prime Minister Nick Clegg’s claim in Edinburgh last week that the UK sector was not “under serious threat” from the Treasury’s move.

The 2011 International Annual Energy Survey, conducted by industry employment specialist Maxwell Drummond, includes the responses of more than 100 international directors from all energy sectors, including operators, service industries, subsea and professional services providers. The full report is being unveiled this weekend at the Offshore Technology Conference (OTC) in Houston, Texas.

The survey shows the Coalition Government’s “supplementary charge” on oil and gas production, projected to add an extra £2 billion to Treasury coffers, significantly and immediately impacted on global perceptions of the already challenging North Sea environment.

Responses elicited before and after the March 23 Budget showed the number of European-based industry leaders who believed that, following the global recession, the oil and gas sector was “back on track” plunged from 62.5% to 45.5%. This contrasts with a slight rise in confidence among operators in rival energy centres, whose positive responses rose from 53.2% to 55.1% in the same timespan.

In addition, before the tax change, 100% of European-based respondents said they believed global exploration and production would be “primarily” in Europe over the next five years. After the Budget, the proportion fell to 66.7%.

Following the Budget, the proportion of European-based respondents who thought Europe would be superseded in 10 years’ time by less mature provinces such as Australasia, Russia, Antarctica, West Africa and Latin America rose from 57.1% to 63.6%.

Speaking from Houston, Tom Faichnie, corporate finance partner at Aberdeen-based accountant Campbell Dallas, who is attending this year’s OTC, told the Sunday Herald that the survey suggested the tax changes were fiscally counter-productive “in the medium to long term” and damaging to Scotland’s oil services sector.

“The industry has been calling for measures to make the North Sea more attractive, in the way that Norway has developed tax-saving schemes to help smaller Norwegian oil companies develop the Norwegian North Sea,” said Faichnie. “It was very surprising to see a tax hike at a time when we should be helping smaller companies.

“Aberdeen and the UK has one of the best servicing sectors in the world, they are very entrepreneurial and fantastic at solving problems, which is why our skills are so exportable. If reserves are not being developed in the North Sea, these technologies may not be developed [in Scotland].

“We can’t afford to ignore this very important survey. It shows tangible evidence of U-turns from companies who will now defer spending in the North Sea, and the repercussions could lead to projects being cancelled.”

Sean Buchan, UK general manager of Maxwell Drummond, said: “The survey has read the mood of industry leaders and clearly there is a significant change of perception of the North Sea.

“The upside from the report is that a number of regionally-focused independents still see opportunities, but it is a fair assumption that some of the bigger operators who are assessing investment internationally will follow Statoil, which decided not to go ahead with a £3bn heavy oil project [following the Budget].”

In response to the survey, a Treasury spokesperson said: “The Government announced a reduction in fuel duty at the Budget and that has to be fully funded, so we will progress with our plans. We are now looking at how we put in place the fair fuel stabiliser and we are working with the industry to make sure we can do that in a responsible way.”