NEW YORK (Reuters) - Oil prices fell back on Monday as weak manufacturing data from the United States, Europe and China reinforced concerns about slowing economic growth and a resulting curb on demand for petroleum.
In choppy trading, losses grew smaller on news that Iran's National Security and Foreign Policy Committee had drafted a bill calling for Iran to try to stop oil tankers from shipping crude through the Strait of Hormuz.
Ongoing concern about the euro zone crisis also pressured oil as enthusiasm for an EU bank bailout deal faded after the agreement had helped push crude prices on Friday to their fourth-biggest daily gain on record.
But crude received support from a strike by Norwegian offshore oil workers now in its second week.
Brent August crude fell $1.50 to $96.30 a barrel by 11:23 a.m. EDT (1523 GMT), having swung from $95.30 to $97.87.
U.S. August crude lost $1.90 at $83.06 a barrel.
On Friday, Brent rose more than $6 a barrel while U.S. crude jumped more than $7, their fourth-largest daily gains in dollar terms since the contracts were launched.
"Oil is being driven by psychological factors," said Eugen Weinberg, global head of commodities research at Commerzbank in Frankfurt. "Today's selloff is a natural reaction after such enormous gains at the end of last week."
Trading volumes for Brent outpaced U.S. turnover, though dealings for both contracts were well below their 30-day averages approaching midday in New York.
(Additional reporting by Gene Ramos in New York and Christopher Johnson in London; Editing by Dale Hudson)
