Traders working at the London Metal Exchange in London, UK (Reuters)

The London Metal Exchange delayed the start of trading in Asia by 90 minutes on Wednesday, with its electronic platform opening at 9:30 AM Beijing time instead of the usual 8 AM.

According to traders at the exchange, some brokers circulated messages about the delay without providing reasons.

After the delayed start, the three-month copper futures contracts in London rose to their highest level since March.