* Oil slips in volatile trade, demand worries in focus
* Iran says U.S. presence at nuclear talks "positive"
* Losses limited by supply problems in Nigeria, Canada
(Updates throughout, changes dateline from LONDON)
NEW YORK, July 17 (Reuters) - Oil prices slipped on
Thursday, adding to a decline of more than $10 this week, on
worries over U.S. demand and easing political tensions between
Iran and the West over its nuclear program.
Thursday's losses were limited, however, by fresh supply
disruptions in Nigeria and Canada that together pulled nearly
200,000 barrels per day off the market.
U.S. crude <CLc1> fell 78 cents to $133.82 a barrel at 1620
GMT. It slid $4.14 on Wednesday, taking the drop from last
Friday's all-time peak of $147.27 to more than $10.
London Brent crude <LCOc1> fell 71 cents to $135.10 a
barrel.
Dealers said the bulk of the downward push on crude oil in
recent days has been concern that mounting economic trouble in
the United States was cutting deeply into demand for fuel in
the world's biggest energy consumer.
"Consumers are being pinched between higher costs for
necessities and lower real wages. The end result is falling
demand almost across the board," said Peter Beutel, president
of Cameron Hanover.
A U.S. government report Wednesday showed U.S. oil product
demand over the past four weeks running 2 percent below a year
ago in a sign soaring pump prices were hitting consumption.
Dealers added that apparent easing tensions between the
United States and Iran over its nuclear program have reduced
some of the geopolitical risk premium in the oil market.
The United States said on Wednesday it was sending an envoy
to Geneva to join nuclear talks with OPEC-member Iran for the
first time, to underline to the Islamic Republic and others
that Washington wanted a diplomatic solution to the impasse.
Iran's foreign minister said on Thursday U.S. participation
in the nuclear talks was "positive."
Trimming oil's losses on Thursday was news that an attack
on an oil pipeline in Nigeria, the world's eighth-biggest oil
exporter, shut 20,000 barrels per day of crude production.
[]
Italian oil company Eni said it had temporarily shut down
production of 47,000 bpd of production in Nigeria because of
loss of pressure in pipelines.
In Canada, Suncor Energy Inc <SU.TO> said a leak at a
pipeline carrying synthetic crude and diesel from its oil sands
fields in Alberta forced a halt of about 140,000 bpd of
shipments. []
Oil prices remain up about 35 percent this year, and up
more than sixfold since 2002, driven in part by surging demand
from developing economies in Asia and worries that world
production growth won't be able to keep pace.
(Reporting by Santosh Menon in London, Luke Pachymuthu in
Singapore and Gene Ramos in New York; Editing by Walter
Bagley)
