Nov 23 (Reuters) - Shanghai zinc prices firmed on Tuesday, hitting their highest levels in nearly three weeks, on global supply concerns after miner and commodity trader Glencore announched plans to put its zinc sulphide operations in Italy under maintenance.

The most-traded January zinc contract on the Shanghai Futures Exchange was up 3.5% at 23,710 yuan a tonne, as of 0748 GMT. It touched its highest since Nov. 4 of 23,980 yuan a tonne earlier in the session.

Three-month zinc on the London Metal Exchange edged 0.2% higher to $3,355.50 a tonne, having earlier hit a more than two-week high of $3,359.

Glencore said the zinc plant in Portovesme, which has a capacity of 100,000 tonnes a year, would be put on care and maintenance until there was "a meaningful change in power market prices".

"The driving momentum is mainly from the European market because there are some potential risks for cutbacks at smelters due to the energy issue," said CRU analyst Dina Yu in China.

However, the Chinese market fundamentals are not good, Yu said, adding supply was increasing with lower disruption from power restrictions while demand from housing and construction sectors had weakened.

The premium of LME cash zinc over the three-month contract rose to $52.80 a tonne, its highest since Oct. 29, indicating tightening nearby supplies as LME inventories of the metal fell to 175,025 tonnes, their lowest since July 2020.

"We see the net impact of high power prices as bullish for aluminium, and zinc, as it drives up marginal costs and may result in further output closures," Citi analysts said in a note.

FUNDAMENTALS

* ShFE copper was up 0.4% at 70,740 yuan a tonne, aluminium was steady at 19,135 yuan a tonne and nickel climbed 3.2% to 152,750 yuan a tonne.

* LME copper slipped 0.4% to $9,686 a tonne, aluminium rose 0.2% to $2,695 a tonne, nickel gained 0.5% to $20,435 a tonne and lead eased 0.4% to $2,250 a tonne.

* The global world refined copper market showed a 52,000 tonnes surplus in August, compared with a 39,000 tonnes deficit in July, the International Copper Study Group (ICSG) said.

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($1 = 6.3845 Chinese yuan) (Reporting by Eileen Soreng in Bengaluru; Editing by Sherry Jacob-Phillips and Subhranshu Sahu)