WHEN in a hole, first, stop digging It's the sort of homespun wisdom which these days appears on fridge magnets. Yesterday Greenpeace boss Chris Rose invoked the little gem (which he credits to Denis Healey) to explain why three of his protesters have taken up residence on Rockall, a smelly and barren lump of rock 289 miles west of mainland Scotland.

Not that Al, Peter, and Meike will be in a position to do any digging, as they squat in their yellow pod, perched on the wave-washed rockface. However, the trio are veterans of the occupation of the Brent Spar platform, which showed that a small environmental lobby group could take on the might of the oil industry and win. The UK Government can have its rock back when it halts oil exploration in the Atlantic Frontier, said Greenpeace yesterday.

Of course, nobody is pretending that if Shell, BP, and the 30 other companies exploring or intending to explore for oil in this area west of Shetland stopped drilling, there would be a major impact on world carbon dioxide emissions. Foinaven, the only one of the four Atlantic Frontier fields close to production, will account for just 0.14% of world supplies. That amounts to about 95,000 barrels a day, compared with the 2.5m barrels that come ashore daily from Scottish waters alone.

The real argument is about whether oil companies should be allowed to look for more oil when UN scientists have said three quarters of all existing reserves must stay undergroumd to prevent climate change. The Greenpeace "sane energy" campaign also calls for a diversion of investment towards renewable energy sources. "We're not saying, 'Shut down the oil industry now'. We're saying that oil, gas and coal have to be phased out," says Rose.

Yesterday, Robert Wine, spokesman for BP Exploration, prime movers in the Foinaven field, said they agreed about the need to tackle climate change, but it had to be done "between governments". And he added: "We agree that it's an issue. Where we disagree is how much of a difference our very little oilfield is going to make." At present oil industry stance is that if economic growth amd rising living standards are to be sustained, there is no alternative to the continued use of fossil fuels.

YESTERDAY the Scottish Council Development and Industry warned of the damaging effects of abandoning the Atlantic Frontiers. North-East area manager, Dugald Cantley, said closure of operations would mean writing off the $1bn already invested, job losses, and the premature run-down of the UK oil and gas industry.

John Wils, Aberdeen director of the UK Offshore Operators Association, said curtailing exploration would mean the oil would be produced somewhere else "in a less environmentally friendly manner".

Behind the scenes the story is somewhat different. Oil production from Foinaven has been put back because of a series of technical problems with the specially designed FPSO, a ship partly constructed from the remains of a Russian submarine tender vessel, which processes the oil and gas pumped up from the seabed and stores it until it can be offloaded on to tankers.

Concerns have been raised about both the risk of a major spillage and the health and safety of the crew, following a number of accidents. Meanwhile, the oil industry is in the process of repositioning itself. While some companies, notably Exxon, continue to deny any link between carbon dioxide emissions and climate change, others are investing heavily in the renewables market. John Brown, chief executive of BP, recently promised that BP Solar, already the second largest global producer of solar panels, would increase sales to $1bn a year.

The next day Heinz Rothermund, managing director of Shell UK Exploration and Production, told a Glasgow audience that despite their emotive language, Greenpeace had raised a key issue.

Of course, Greenpeace's real target is the Government. They say the apparent willingness of the DTI to grant more licences to exploration companies operating on the Atlantic Frontier contradicts Tony Blair's pledge to press world governments for big cuts in carbon dioxide emissions at the forthcoming Earth Summit Two and is threatening to take Margaret Beckett to court over the issue.

Above everything, Greenpeace hopes pressure from the Rockall protest may push the Government into raising the emissions issue at the G7 summit.