The ban is not yet effective.
But this week, the Trump administration just made its most important move against Huawei yet.
China retaliated with higher tariffs on a revised list of $60 billion (47 billion pounds) worth of USA products.
Over the past year, many US agencies have been warning the administration of the security and espionage threats posed by Huawei and other Chinese companies.
On the other hand, USA companies like Apple face the risk of severe retaliation from China, a key market. Huawei is the second-biggest smartphone vendor in the world, according to IDC, and it sells a large amount of network equipment to telecom providers and other companies.
Roundup Huawei has been kicked by a U.S. national emergency proclamation hitting "foreign" gear, spent some cash in France, claimed it's worth billions to Britain and was described as "a potential security risk" by a former head of MI6.
A Trump administration decision to restrict the sale of USA technology to Chinese telecommunications company Huawei will disrupt global supply chains, say analysts, ramping up pressure on US allies reluctant to join in efforts to shut out Huawei from advanced 5G mobile networks.
"They can relatively better manage component sourcing for mobile phones because they have their own component businesses for smartphones". Joseph Franell, the company's chief executive officer, said in an interview on Thursday.
In what some have compared to the Cold War arms race, the United States is anxious that 5G dominance would give any global competitor such as China an advantage Washington is not ready to accept.
Its initial target was to build inventories of six to nine months, and it has recently been raised to 12 and, in some cases, 24 months, Jefferies said.
"The China government doesn't speak for us and we don't speak through the Chinese government".
South Korea's Samsung dropped 2.4%, SK Hynix fell 3.5%, while China's Luxshare Precision Industry fell as much as 6.1%.
Why? Because Huawei uses components from a bunch of United States chipmakers, who will now either have to stop serving the tech giant or apply for a licence, details of which are not clear. "What we have prepared has already been used in some of our products in the Chinese market".
In a move that will likely add fire to the growing trade war between the U.S. and China, President Trump has declared a "national emergency" to protect U.S. communication networks. -China trade war stalled last week, the United States ramped up the pressure by raising tariffs on a list of $200 billion worth of Chinese imports to 25% from 10%.
Huawei, founded in 1987 by a former engineer in China's People's Liberation Army, denies it spies for Beijing, says it complies with the law and that the United States is trying to smear it because Western companies are falling behind.
Stock markets have been hit by the row but have steadied in recent days amid hopes the two countries might hold talks.
First, the White House issued an "Executive Order on Securing the Information and Communications Technology and Services Supply Chain", which boils down to granting the executive branch massive power to veto the use of "information and communications technology or services designed, developed, manufactured, or supplied, by persons owned by, controlled by, or subject to the jurisdiction or direction of a foreign adversary".
The Commerce Department issued a rule, promised on Wednesday, putting Huawei and 68 affiliates in more than two dozen countries on its so-called entity list, a move that bans the company from buying parts and components from American firms without USA government approval.
"Let us make one thing clear: you can criticise many things about the Trump administration, (but) there is effectively zero doubt Huawei is a branch of the PLA and actively engages in espionage for Beijing", he tweeted.