Xcite Energy Share News (XEL)

Oil companies are still reeling from yesterday's Budget decision to increase the tax paid on North Sea oil and gas production to subsidise a 1p a litre cut in fuel duty.North Sea focused oil producer Enquest slumped on the news and is down again today. Encore Oil suffered a less dramatic post-Budget dive, but remains in the red Thursday.Nautical Petroleum, Valiant, Faroe Petroleum and Xcite Energy are also among the casualties as the Supplementary Corporation Tax (SCT) grows from 20% to 32%. Big players like BP have weathered the storm. Although their interests in the area are huge - it's responsible for about 11% of UK production - the impact is more modest relative to its global production, says Westhouse Securities.Barclays Capital thinks BG Group will be among the most impacted - about 4% of annual earnings - as the North Sea accounts for almost a quarter of total operations.Analysts over at Evolution have sprung to the defence of Premier Oil, finder of the potentially massive Catcher field.They reckon it will be able to offset US$1.1bn of Oilexco tax losses against the new marginal tax rate of 62%, up from 50%, above $75 a barrel (bbl).At $90/bbl the net present value (NPV) impact of the higher tax on Premier is $80m or 40p/ a share, half yesterday's share price fall.LW