April 23 (Reuters) - Copper slid on Thursday after

hitting over seven-week highs, as the U.S. dollar strengthened

and risk appetite came under pressure amid uncertainties

surrounding the Middle East peace talks.

The benchmark three-month copper on the London Metal

Exchange lost 1.44% to $13,239 a metric ton as of 0255 GMT,

after pulling 0.36% higher to $13,481.50, the highest since

February 27.

And the most-active copper contract on the Shanghai

Futures Exchange nudged 0.05% lower to 102,420 yuan ($14,990.56)

a ton, paring gains after rising as much as 1.65%.

The earlier gains were thanks to U.S. President Donald Trump

extending a ceasefire with Iran and renewed premium of Comex

copper prices over the LME benchmark.

Thursday's whipsaw move came as the outlook for the

ceasefire and the prospect of an Iran peace deal remained

uncertain.

Iran has yet to confirm the extension, and the U.S.

continued its blockade of Iranian ports, a move that is

considered the main choke point by the Iranian negotiators for

further talks.

Adding to the lack of confidence was Iran's latest move to seize

ships in the Strait of Hormuz, tightening its grip on the key

waterway.

Oil price jumped, with the Brent future climbing

above $100 a barrel. Higher energy prices hurt the outlook for

industrial metals by fanning inflation and growth fears.

Rising concerns over a lack of sulphuric acid is pointing to

rising supply concerns over copper.

China's customs data showed its sulphuric acid export to its

biggest overseas acid market, Chile, had dried up in March, even

before China's export ban kicked off in May, leaving the world's

top copper-producing country in a squeeze on the supply of the

chemical used to make around half of its refined metal.

Elsewhere, most base metals declined.

Among other metals on the LME, aluminium dropped

0.73%, zinc shed 0.68%, lead lost 0.79%, nickel

tumbled 1.34% and tin slid 1.29%.

On SHFE, zinc posted sole gain at 0.41%. aluminium

dipped 0.20%, lead lost 0.86%, nickel

dropped 0.36% and tin shed 0.91%.

Thursday, April 22

DATA/EVENTS (GMT)

0645 France Business Climate Mfg, Overall Apr

0715 France HCOB Mfg, Services, Composite Flash PMI

Apr

0730 Germany HCOB Mfg, Services, Composite Flash PMI

Apr

0800 EU HCOB Mfg, Services, Composite Flash PMI Apr

0830 UK Flash Manufacturing, Services, Composite PMI

Apr

1000 UK CBI Business Optimism Q2

1230 US Initial Jobless Clm 18 Apr, w/e

1345 US S&P Global Mfg, Scvs, Comp PMI Flash Apr

($1 = 6.8323 Chinese yuan renminbi)