Following the turmoil in international oil markets, Bank of China?suspended?on Wednesday the opening of new positions in a structured crude oil trading product for retail investors linked to international futures contracts, including WTI Crude and Brent Crude.??

New positions cannot be opened from Wednesday of the crude oil ?bao', or treasury, product, which Bank of China sells to individual clients, in view of ?current market and delivery risks,? the bank said in a statement carried by Reuters.

Bank of China suspended trading in its two crude oil products linked to the U.S. crude benchmark for one day on Tuesday.

On Monday, the WTI Crude May futures contract?crumbled by more than 300% to settle at -$37 a barrel, under intense pressure a day before the contract expired, but also reflecting market fears that storage in the U.S. would soon fill. The futures contract crashed into negative territory for the first time as traders rushed to get rid of the May contract to avoid owning physical oil barrels for May delivery.

The historic collapse in the WTI Crude May contract wreaked havoc on all oil-linked traded products, including funds tracking crude prices.

The United States Oil Fund LP (NYSEARCA: USO) - an ETF for crude ? said in an SEC filing on Tuesday that it was?suspending?the ability of the USO Authorized Purchasers to purchase new creation baskets, which halted new trades after the 300% collapse in WTI Crude May futures contract on Monday.??

Pierre Andurand, a well-known energy trader, warned traders on Tuesday of massive losses in ETFs.

?I think the CME might have no other choice but to close out the ETFs positions. It cannot take the risk to have negative prices before the roll and be on the hook. This shock is real. Be very careful out there. We are going to hear about crazy losses in the days and weeks to come,? Andurand?said?on Twitter on Tuesday.??

By Tsvetana Paraskova for Oilprice.com

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