METALS-London copper falls after hitting five-month high above $10,000 mark

(Updates prices) By Polina Devitt LONDON, March 20 (Reuters) - London copper prices hit a five-month high on Thursday, breaking above a psychological mark of $10,000 per metric ton before retreating under pressure from a stronger dollar and producer selling. Benchmark three-month copper CMCU3 on the London Metal Exchange (LME) fell 0.7% to $9,920 a ton by 1737 GMT after touching $10,046.50, its highest since October 3. Supporting the high London price were the most-active May copper futures on the U.S. Comex exchange HGc3 , which were last up 0.1% at $5.1065 a pound after hitting a 10-month high. Comex copper is up 27% this year compared to the LME benchmark's growth of 14%, as the United States considers imposing new import tariffs on copper. U.S. President Donald Trump's 25% tariffs on steel and aluminium products took effect last week. The premium of the Comex most-active contract was last at a record high of $1,344 per ton. Due to this wide premium and the tariff threat itself, much copper is heading to the United States, a source at a U.S. warehouse operator said. The flows into the U.S. are tightening non-U.S. markets for copper, which is used in power and construction. However, any backtracking on U.S. tariffs could drive down the premium and U.S. import demand, Morgan Stanley said in a note. Comex copper stocks HG-STX-COMEX are down 7.5% since mid-February to 93,154 tons, but outflows from the LME copper stocks continue, daily LME data showed. The copper stocks in LME-registered warehouses MCUSTX-TOTAL are at 223,275 tons, their lowest since mid-July. Meanwhile, the dollar rose a day after the Federal Reserve indicated it was in no rush to cut rates due to uncertainties about U.S. tariffs. A stronger U.S. currency makes dollar-priced metals more expensive for buyers using other currencies. FRX/ LME aluminium CMAL3 fell 0.5% to $2,657 a ton and zinc CMZN3 was steady at $2,924. Daily LME data showed massive fresh cancellations, bringing the cancelled stocks to 60% of the total for both metals. 0#MALSTX-LOC 0#MZNSTX-LOC The cancellations indicate only the intention to remove the product from the LME system, and the metal can be put back on warrant. LME lead CMPB3 slid 1.5% to $2,053.50, tin CMSN3 rose 0.7% to $35,277 and nickel lost 0.8% to $16,270. (Reporting by Polina Devitt; Additional reporting by Violet Li; Editing by Shounak Dasgupta, Joe Bavier and Rod Nickel) ((polina.devitt@thomsonreuters.com; Reuters Messaging: polina.devitt.thomsonreuters.com@reuters.net)) (( For related news and prices, click on the codes in brackets: LME price overview RING= COMEX copper futures 0#HG: All metals news MTL All commodities news C Foreign exchange rates FX= SPEED GUIDES LME/INDEX ))