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LONDON, Oct 6 (Reuters) - Oil markets are beginning torecover but the scale of global oversupply means prices may riseonly slowly, the chief executive of Royal Dutch Shell Plc said on Tuesday.
"I see the first mixed signs for recovery of oil prices,"Ben van Beurden told an oil industry conference in London.
"But with U.S. shale oil being more resilient than weoriginally thought and a lot of oil still in stock, it will takesome more time to rebalance demand and supply," he added.
Oil prices have collapsed over the last year in the face ofheavy oversupply, with benchmark Brent crude falling tobelow $50 a barrel from a high above $115 in June 2014.
The Organization of the Petroleum Exporting Countries led bySaudi Arabia has increased production in an attempt to buildmarket share, leaving some other producers, including shalecompanies in North America, operating below break-even costs.
Van Beurden said many U.S. oil producers would struggle torefinance while prices remained so low, leading to lower outputin the future: "Producers are now looking for new cash tosurvive and they will probably struggle to get it."
Longer-term, there was a risk that low levels of globalproduction could bring a spike in oil prices, he said.
If prices remained low for a long time and oil productionoutside OPEC and the United States declined due to cuts tocapital expenditure, there was not likely to be any significantspare capacity left in the system, he said.
"This could cause prices to spike upwards, starting a newcycle of strong production growth in U.S. shale oil andsubsequent volatility," van Beurden said. (Reporting by Ron Bousso; Editing by Christopher Johnson andDale Hudson)