BEIJING - China released another 150 000 t of state metal inventories to the market on Wednesday, its reserves administration said, completing a third round of auctions so far this year as it aims to ease the pressure of high commodity prices on businesses.

The sales, which began in early July, are the first in more than a decade. They come as prices of many commodities have hit records in 2021 and President Xi Jinping has called for China to better manage its state reserves system.

The world's leading metals consumer offered processors and manufacturers the chance to bid on Wednesday for 30 000 t of copper, 70 000 t of aluminium and 50 000 t of zinc reserves, which were sold in small batches on online platforms.

Visibility on the auctions was limited but all the copper was sold off well before the end of the morning session, with sales at a discount of at least 1 300 to 1 500 yuan ($20 to -$232) per tonne to market prices, industry data provider Shanghai Metal Exchange Market (SHMET) said.

Copper on the Shanghai Futures Exchange closed down 1.8% at 68 900 yuan ($10 653) a tonne on Wednesday.

The latest round brings the total amount of metal released by the National Food and Strategic Reserves Administration in the past two months to 420 000 t.

In a statement, the administration said it would continue to offer metal reserves based on market supply, demand and prices.

Shanghai aluminium prices hit a 13-year high this week.

In a top-level meeting on Monday, Xi underlined the importance of managing state reserves and said the country would build a unified strategic and emergency reserves system.

China "is a big country and must have strength in national reserves and emergency response capabilities that match the status of a big country," a state media readout of Monday's meeting said.

China has released several million tonnes of coal reserves to the market this year and auctioned hundreds of thousands of tonnes of corn reserves in an effort to tame high prices. .

To prop up low hog prices and help loss-making farmers, meanwhile, it has also bought tens of thousands of tonnes of domestically produced pork for state reserves..