IT is only oil and gas fields that have come on stream in the past year that have kept North Sea production rising, according to the latest Royal Bank of Scotland oil and gas index.

The findings will put further pressure on the Government as it considers the fiscal review of the North Sea industry, the uncertainty of which has already prompted BP to put its Clair field west of Shetland on hold.

Oil output in April was only 43,000 barrels a day higher than a year earlier, though production in April from the nine new fields totalled 275,000 barrels a day or just over 10% of oil production. The output from older fields was down by 7.4% to 187,000 barrels.

Similarly, gas production in April was 8% up on a year ago at 676 million cubic feet, thanks to three new gas fields which added 734 million cubic feet to production.

Stephen Boyle, head of business economics at the Royal Bank of Scotland, said: ''The contribution of new fields is clear - without them production would be in decline. This reflects the need for a continuing stream of new developments if output levels, company incomes and Government tax revenues from the UK continental shelf and contracts for the service and supply industry are to be maintained.''

Foinaven, the first west of Shetland field to come on stream, is the single-biggest contributor among the new fields, averaging 64,000 barrels a day in April, up by one-third from March.

Combined daily oil and gas revenues fell again, reaching their lowest level since last July at #37.4m.

Oil prices rose 2.7% in April to $13.53, but on an annual basis are down by 23.6% and in sterling terms prices were 25.6% lower than in April 1997.

q WORLD oil prices surged yesterday after oil producers convened secret talks in Amsterdam to consider further cuts in crude supply to a glutted market.

Benchmark Brent blend for July loading stood 54 cents a barrel higher at $14.58 a barrel.