The impact of the Trump administration’s threats to choke Huawei Technologies Co. reverberated across the global supply chain on Monday, hitting some of the biggest component-makers.

Chipmakers including Intel Corp., Qualcomm Inc., Xilinx Inc. and Broadcom Inc. have told their employees they will not supply Huawei until further notice, according to people familiar with their actions. Alphabet Inc.’s Google cut off the supply of hardware and some software services to the Chinese mobile phone equipment giant, another person familiar said, asking not to be identified discussing private matters.

The Trump administration on Friday blacklisted Huawei — which it accuses of aiding Beijing in espionage — and threatened to cut it off from the U.S. software and semiconductors it needs to make its products. The ban, which had been anticipated, hamstrings the world’s largest provider of networking gear and No. 2 smartphone vendor.

Blocking the sale to Huawei of critical components could also disrupt the businesses of American chip giants like Micron Technology Inc. and retard the rollout of critical 5G wireless networks worldwide — including in China. That in turn could hurt U.S. companies that are increasingly reliant on the world’s second largest economy for growth.

Chipmakers and other companies are under pressure in part because they will lose revenue when they cut off Huawei as a customer. But the tech industry is also poised to suffer in a more fundamental way. Huawei depends on many U.S. companies for components woven into the 5G equipment it makes.

Given a dearth of competitors capable of making 5G gear as reliable and inexpensive, any impediment to Huawei’s production of this equipment could slow the rollout and adoption of 5G technologies. That in turn could damp demand for smartphones and networking equipment and may also hinder the development of new technology that will depend on 5G, such as self-driving cars.

If fully implemented, the Trump administration action could have ripple effects across the global semiconductor industry. Intel is the main supplier of server chips to the Chinese company, Qualcomm provides it with processors and modems for many of its smartphones, Xilinx sells programmable chips used in networking and Broadcom is a supplier of switching chips, another key component in some types of networking machinery. Representatives for the chipmakers declined to comment.

Intel, which gets less than 1 percent of its revenue from Huawei according to Bloomberg supply chain data, fell 2 percent in New York Monday. Qualcomm, which gets about 2.6 percent of its revenue from Huawei, fell 4.8 percent. Lumentum Holdings Inc. cut its fourth-quarter forecast and said it has discontinued all shipments to Huawei, which accounts for about 18 percent of its sales. Its shares fell 3.7 percent. Broadcom, with 5.3-percent revenue exposure to Huawei, was down 4.4 percent.

In Europe, the impact of the ban was also being felt, though companies there are only restricted from supplying research or products made in the U.S. Germany’s Infineon Technologies AG fell as much as 6 percent after the Nikkei reported it halted shipments to the Chinese company in the wake of the U.S. ban. Shares of STMicroelectronics NV and Austrian-based AMS AG were also hit.

An Infineon spokesman said that the majority of products it delivers to Huawei are not subject to U.S. restrictions, adding that the chipmaker can "make adaptations in our international supply chain." AMS also said that it had not suspended shipments to Huawei.

Huawei “is heavily dependent on U.S. semiconductor products and would be seriously crippled without supply of key U.S. components,” said Ryan Koontz, an analyst with Rosenblatt Securities Inc. The U.S. ban “may cause China to delay its 5G network build until the ban is lifted, having an impact on many global component suppliers.”

Morgan Stanley analysts wrote Monday that semiconductor investors should reduce their positions, with a prolonged re-escalation of U.S.-China trade tensions not yet discounted by the U.S. equity market.

Huawei’s $500m bond due 2027 was indicated 0.3 cents on the dollar lower at 93.8 cents at 2 p.m. in Hong Kong, according to Bloomberg-compiled prices. That’s after it posted a record drop of 2.4 cents on Friday. The ban’s commencement also walloped shares of Asian tech supply chain companies Monday. Sunny Optical Technology Group Co. was again the worst performer on Hong Kong’s Hang Seng Index, while Luxshare Precision Industry Co. dived as much as 9.8 percent in Shenzhen.

To be sure, Huawei is said to have stockpiled enough chips and other vital components to keep its business running for at least three months. It’s been preparing for such an eventuality since at least the middle of 2018, hoarding components while designing its own chips, people familiar with the matter said. But executives believe their company has become a bargaining chip in ongoing U.S.-Chinese trade negotiations, and that they will be able to resume buying from American suppliers if a trade deal is reached, they said.

The American companies’ moves are likely to escalate tensions between Washington and Beijing, elevating fears that President Donald Trump’s goal is to contain China, triggering a protracted cold war between the world’s biggest economies. In addition to a trade fight that has rattled global markets for months, the U.S. has pressured both allies and foes to avoid using Huawei for 5G networks that will form the backbone of the modern economy.

“The extreme scenario of Huawei’s telecom network unit failing would set China back many years and might even be viewed as an act of war by China,” Koontz wrote. “Such a failure would have massive global telecom market implications.”

U.S. spy chiefs have in past days briefed American companies, investors and other important groups on the dangers of doing business with China, the Financial Times reported Monday.

The American clampdown also deals a direct blow to Huawei’s fast-growing mobile devices division. Huawei will only be able to access the public version of Google’s Android mobile operating system, the world’s most popular smartphone software. It won’t be able to offer proprietary apps and services from Maps and search to Gmail, said the person, who requested anonymity speaking about a private matter. That will severely curtail the sale of Huawei smartphones abroad, though it’s unclear when those apps — which are popular mainly outside of China — will become unavailable.

Huawei, the world’s largest smartphone brand after Samsung Electronics Co., was one of a select few global hardware partners to receive early access to the latest Android software and features from Google. Outside of China, those ties are critical for the search giant to spread its consumer apps and bolster its mobile ads business. Huawei said it will continue to provide security updates and sales services to customers using Google’s Android operating system, according to a company statement Monday.

The Chinese company will still have access to app and security updates that come with the open-source version of Android. Reuters reported the move earlier. “We are complying with the order and reviewing the implications,” a Google representative said, without elaborating.