


Image copyright Getty Images
Image caption Huawei unveiled new phones powered by ARM-based chips, on Tuesday



ARM's designs form the basis of most mobile device processors worldwide.




He said it would greatly affect the firm's ability to develop its own chips, many of which are currently built with ARM’s underlying technology, for which it pays a licence.

These are used in the Chinese company's 5G base stations and computer servers in addition to its smartphones.

Cambridge-headquartered ARM had been described as the UK's largest tech firm until its takeover by a Japanese fund. It employs 6,000 workers and lists eight offices in the US .

In a statement on Wednesday it said: "ARM is complying with the latest restrictions set forth by the US government and is having ongoing conversations with the appropriate US government agencies to ensure we remain compliant.


Huawei has issued a brief statement of its own.

"We value our close relationships with our partners, but recognise the pressure some of them are under, as a result of politically motivated decisions," it said.


What is ARM?

Image copyright ARM



In some cases, manufacturers only license ARM's architecture, or "instruction sets", which determine how processors handle commands. This option gives chip-makers greater freedom to customise their own designs.

In other cases, manufacturers license ARM's processor core designs - which describes how the chips' transistors should be arranged. These blueprints still need to be combined with other elements - such as memory and radios - to create what is referred to as a system-on-chip.

As a result, when you hear talk of a device being powered by a Samsung Exynos, Qualcomm Snapdragon or Apple A11 chip - or one in a Huawei smartphone - it is still ARM's technology that is involved.



‘Unfortunate situation’





Image copyright Huawei
Image caption A break with ARM would make it difficult for Huawei to develop future generations of its Kirin processors



ARM staff that come into contact with employees at industry events must “politely decline and stop” any conversations about the business, the guidance said - stressing that individuals could be held personally liable for breaking the trade rules.


'Insurmountable obstacle'




HiSilicon's upcoming processor, Kirin 985, is due be used in Huawei devices later this year. According to a source at ARM, it is not expected to be affected by the ban. However, the next iteration of the chip has not yet been completed - and is likely to need to be rebuilt from scratch, the source said.



Image copyright
Image caption Huawei's carrier division chief Ryan Ding showed off its 5G base station chip alongside an image saying it involved a "high-performance ARM-based processor"

"The problem of the whole telecoms industry is that so much of it is based on the exchange of technology between different companies - whether that's chip companies, software providers or the makers of other hardware," commented Alan Burkitt-Gray, editor-at-large of the telecoms news site Capacity Media.


"This will carve out a chasm in the industry between Huawei-originated intellectual property and the rest of the world's," he said.

"It's just a total mess and it's happened at a critical time for the rollout of 5G."

The relationship between ARM and Huawei engineers is tight - earlier this month Huawei announced its intention to build a research centre only 15 minutes from ARM’s headquarters in Cambridge, UK.

Image copyright Reuters
Image caption The latest development follows news that Huawei will lose access to some of Google's Android services





"They’re not going to be able to easily replace these parts with new, in-house designs - the semiconductor industry in China is nascent.”


Additional reporting by Leo Kelion

Follow Dave Lee on Twitter @DaveLeeBBC
