Copper prices held steady in London on Wednesday under pressure from concerns about current demand in top metals consumer China, rising stocks and a stronger dollar.

Benchmark copper on the London Metal Exchange (LME) was stable at $9,567 a metric ton in official open-outcry trading. It has dropped 14% since speculative buying took prices to a record high of $11,104.5 on May 20.

"Copper rod or wire rod producers in China have increased production a little bit in June from April-May levels, but this growth has not been significant. It means that demand has not picked up much yet despite copper prices falling from recent highs," said Dan Smith, head of research at Amalgamated Metal Trading.

Copper stockpiles in the LME-registered warehouses kept on rising, with the daily LME data showing 2,700 tons of arrivals which boosted the stocks to 175,475 tonnes, the strongest in more than six months.

The discount for LME cash copper over the three-month contract was at a record high of $148.4.

A stronger U.S. currency kept pressure on dollar-priced metals by making them more expensive for buyers using other currencies. China's yuan weakened to a fresh seven-month low against the dollar.

However, tight copper mine supply may provide an upside to the metal, used in power and construction, in the second half of the year, BofA Securities said in a note.

"The base metals rally that started in January has been fading, repeating a pattern seen in the past two years: investors tend to drive prices up in Q1 and Q2, but as physical demand is slow to catch up, the industrial metals then give back some of the gains."

"That said, this year's fundamental backdrop is much stronger, so we believe the downside is ultimately limited," BofA added.

LME zinc rose 1.4% to $2,912 in official activity and nickel added 0.1% to $17,175. Aluminium was down 0.2% at $2,492, lead fell 0.2% to $2,206 and tin lost 1.4% to $31,800.

(Reporting by Polina Devitt in London; editing by Vijay Kishore, Alexandra Hudson and Louise Heavens)