The British government is seeking new powers that would allow it to ban technology vendors on national security grounds from supplying companies working in the country’s critical sectors — and to potentially do so in secret without publicly identifying the supplier concerned and barring the company from discussing the instruction.

The proposals, published Monday in amendments to the Cyber Security and Resilience Bill, adapt powers previously used to restrict Huawei equipment in Britain’s 5G networks, while removing some of the transparency safeguards built into that regime.