(Recasts with COMEX record high, updates prices at 1450 GMT)

By Eric Onstad

LONDON, July 23 (Reuters) -

U.S. copper prices hit a

record high

on Wednesday as the planned date for U.S. tariffs

approached, while London levels edged up to their strongest in

over two weeks on the back of a U.S.-Japan trade deal.

U.S. COMEX copper futures were up 2.8% to $5.88 a lb

by 1450 GMT after hitting a peak of $5.93 ahead of the planned

August 1 start of 50% tariffs imposed by U.S. President Donald

Trump on imports of the metal.

COMEX copper has gained 32% since February, when Trump

ordered an investigation into copper tariffs.

Benchmark three-month copper on the London Metal

Exchange was little changed at $9,918 a metric ton after earlier

touching its strongest price since July 4 at $9,947.

The premium of COMEX over LME copper surged to over $3,100

a ton, a record.

Sentiment was boosted after U.S. President Donald Trump struck a

trade deal with Japan, lifting global share markets.

Metals investors are focused on a potential trade deal with the

world's top metals consumer China ahead of a meeting scheduled

for next week between U.S. and Chinese officials in Stockholm.

Worries about oversupply, however, weighed on the market,

highlighted by data showing the copper market was in a surplus

of 272,000 metric tons in the first five months of the year.

Also chipping away support was an overhang of inventories in the

U.S. after traders took advantage of the higher COMEX prices.

"We could see ... copper range-trading once the tariffs come

into play or possibly even soften," said Nitesh Shah, commodity

strategist at WisdomTree.

"The U.S. will be using up all that stockpile of copper

before importing new units from abroad and therefore demand may

look a little bit weak for that period of inventory rundown."

Aluminium was the worst performing LME metal,

dropping 0.5% to $2,645.50 a ton.

"I think the producers are quite happy to get on and do a

lot of forward selling around these levels," Robert Montefusco

at broker Sucden Financial told a webinar.

Among other metals, zinc rose 0.2% to $2,865.50,

lead gained 0.7% to $2,025, nickel added 0.1% to

$15,540 and tin jumped 2.2% to $34,655.

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