Amazon Japan has suspended direct online sales of Huawei Technologies Co. products after Washington last week blacklisted the Chinese communications giant, sources close to the matter said Friday.

The e-commerce titan's move came as major Japanese mobile phone service operators such as KDDI Corp. and SoftBank Corp. postponed on Wednesday their plan to launch Huawei's new smartphones — two days before the scheduled date.

Amazon Japan is said to have stopped selling Huawei products it had procured on its own, including the latest smartphone models, personal computers and tablets, citing "concerns over the operating system."

Customers are still able to buy Huawei products sold by other venders on Amazon Japan's e-commerce site.

"We are considering a solution for our customers to safely use" Huawei products, said an Amazon Japan official. But the firm did not disclose when it would resume selling them.

NTT Docomo Inc., the largest wireless carrier by number of users in the country, also said Wednesday it had stopped taking orders for Huawei's high-end model handsets that were previously scheduled to hit the market in the summer.

Many low-cost mobile phone service operators followed the major carriers' moves, but electric appliance retailers Bic Camera Inc. and Yodobashi Camera Co. said they plan to sell Huawei's new smartphones as scheduled.