MANILA, June 8 (Reuters) - London copper retreated on Friday
after a six-day rally that pushed the metal to its strongest in
4-1/2 years in the previous session, amid worries over potential
supply disruptions at the world's biggest copper mine where wage
talks are underway.
    The union of workers at the BHP-operated
Escondida copper mine in Chile last week kicked off labor
negotiations with a contract proposal that includes a bonus of
about $34,000 per worker, sparking fears of a possible strike.

    Three-month copper on the London Metal Exchange was
down 1.4 percent at $7,230 a tonne by 0217 GMT. The contract
touched $7,348 on Thursday, its loftiest since January 2014, and
has risen nearly 5 percent so far this week, the most since
mid-February.
    ANZ senior commodity strategist Daniel Hynes said the
Escondida union's bonus proposal compares with BHP's offer of
$21,300, "therefore, both parties reaching a deal looks
difficult at the moment, leaving room for a strike."
    "The union has enough cash to go on a strike of 44 days.
This deal is important for the other wage contract renewals too.
We see prices remaining volatile until they reach an agreement,"
Hynes said in a report this week.
            
    * SHANGHAI COPPER: The most-traded August copper contract on
the Shanghai Futures Exchange slipped 0.2 percent to
53,840 yuan ($8,411) a tonne.
    * CHINA DATA: China is scheduled to release its trade data
later in the day, with exports and imports expected to have
grown at a firm pace in May but slightly slower than the
previous month.
    * IMPORTS: In April, China's copper imports rose 2.8 percent
from the previous month to 442,000 tonnes.
    * CHILE OUTPUT: Chile's copper production in April jumped
6.4 percent from the same month a year earlier, Chilean copper
commission Cochilco said, boosted by increased output at large,
privately held mines in the world's top copper producer.

    * DOLLAR: The dollar wallowed near a three-week low against
peers as U.S. Treasury yields fell sharply, while the euro's
recovery remained intact amid expectations that the European
Central Bank would begin unwinding it stimulus programme.
    * TRUMP: Leaders of the Group of Seven rich nations headed
for a summit in Canada more divided than at any time in the
group's 42-year history, as U.S. President Donald Trump's
"America First" policies risk causing a global trade war and
deep diplomatic schisms.
    * U.S. DATA: The number of Americans filing for unemployment
benefits unexpectedly fell last week, pointing to a further
tightening in labor market conditions.   
    * OTHER METALS: Other metals also slipped, with LME lead
 down 1.9 percent at $2,482.50 a tonne, after hitting a
three-month high on Thursday, and zinc dropping 0.9
percent to $3,155.50. Shanghai lead fell 1.4 percent to
20,375 yuan a tonne and nickel lost 1.9 percent to
115,680 yuan.