* Copper inventories at lowest level since March
* Aluminium spread eases on plentiful supplies (Adds analyst comment, updates prices, changes dateline from BEIJING)
LONDON, Jan 7 (Reuters) - Copper prices clawed higher on Tuesday as U.S.-Iran tensions eased and investors expected leading metals consumer China to extend its stimulus policies.
Global equities steadied and oil pulled back from multi-month highs as investors judged the prospects of an all-out conflict between the United States and Iran had eased.
"The wider markets have paused, the equity moves have stabilised. I think everyone is now taking stock," said Colin Hamilton, director of commodities research at BMO Capital in London.
"Even though we've seen tensions rise, the fact that China is still supportive is certainly helping industrial metals. It's been petty clear that the Chinese policy dynamics are still supporting growth and investment."
Data last week showed that Chinese business confidence shot up in December, lifting investor sentiment even though factory activity expanded at a slower clip.
Three-month copper on the London Metal Exchange (LME) was up 0.3% at $6,155 a tonne by 1040 GMT, extending a 0.2% gain in the previous session.
The most-traded March copper contract on the Shanghai Futures Exchange closed 0.4% up at 49,010 yuan ($7,050.48) a tonne.
* COPPER STOCKS: Copper inventories in LME-monitored warehouses <MCU-STOCKS> have slumped by almost 60% since late August and are currently at 140,925 tonnes, the lowest since March 2019.
Copper stocks have been low for a while, "but the reality is no one has felt the need to chase prices higher", said Guy Wolf, global head of market analytics at brokerage Marex Spectron in Singapore.
"Without resolution on the tariff situation, no one is really going to feel the need to risk-up and start filling the supply chain again."
* ALUMINIUM SPREAD: LME cash aluminium's discount to the benchmark three-month contract <CMAL0-3> increased to $33 a tonne, its highest since September last year, having swung from a premium of $22.75 early last month. That indicates healthy supplies of metal for near-term use in the LME warehouse system.
LME aluminium was the only metal in the red, slipping 0.3% after hitting its highest since July 22 on Monday.
* BAUXITE: Aluminum Corp of China (Chalco) has shipped the first cargo of bauxite from its Boffa mine in Guinea, a company spokesman said.
* PRICES: LME nickel rose 0.6% to $13,900 a tonne, zinc gained 0.5% to $2,337, lead was up 0.4% at $1,928 and tin climbed 0.4% to $16,910. ($1 = 6.9513 yuan) (Additional reporting by Tom Daly in Beijing Editing by David Goodman)