The remaining lifespan of the UK’s North Sea oil and gas production risks being halved as the economic crisis has prompted a plunge in exploration in one of the western world’s most important deposits, the industry has warned.

The number of exploration wells being drilled in the North Sea has collapsed by 78 per cent in the first quarter of 2009 compared with the same period last year, according to the most recent industry data from Deloitte, the accounting and consulting firm.