Brent crude, which has more than halved in the past year, stabilised in March. But it has come under renewed pressure after the price fell below US$55 a barrel this month - a 20 per cent decline from a five-month high reached in early May.
Investors have been nervously watching the sector after the S&P energy index fell more than 7 per cent in the past month.
The rout in other commodity prices has also hurt mining companies, which are slashing jobs and shutting operations as they try to cope with the fallout of the end of the gold and copper boom.
Among companies postponing big production plans while waiting for costs to come down are UK-listed BP, Anglo-Dutch Royal Dutch Shell, US-based Chevron, Norway's Statoil, and Australia's Woodside Petroleum.
More than half the reserves put on hold lie thousands of metres under the sea, including in the Gulf of Mexico and off west Africa, where the technical demands of extracting crude and earlier inflation have pushed up costs.
Canada is the biggest single region affected, with the development of 5.6 billion barrels of reserves, almost all oil sands, having been deferred.
"The upstream industry is winding back its investment in big pre-final investment decision developments as fast as it can," Wood Mackenzie said in a report.
"This is partly because it is one of the quickest ways to free up capital in response to low oil prices."
It added that the number of large upstream projects expected to be fully approved during 2015 could probably be counted "on one hand".
Shell is in the process of making deeper cuts to its capital spending this year, cutting its most recent estimate of US$33 billion expenditure.
France's Total is expected to reveal that it has managed greater efficiency savings than expected just a few months ago, while BP is likely to spell out the impact of falling supplier costs on its spending.
- The Financial Times
