The European Union has warned that 5G networks could be left vulnerable to attack from state-backed hackers if operators use too many parts from a single supplier.
A report from the bloc released Wednesday says that mobile network operators should not rely too heavily on suppliers that have "a strong link" to governments that lack "democratic checks and balances."
"In this context of increased exposure to attacks facilitated by suppliers, the risk profile of individual suppliers will become particularly important," EU officials said in a statement.
While the document does not specifically mention China's Huawei, its publication follows an intense campaign by the United States designed to discourage allies from using the company's 5G equipment.
The United States says that Huawei products pose a national security risk because they could be used by Beijing for spying. Huawei has denied the accusations, and called on the Trump administration to provide evidence to back up its claims.
Europe has so far resisted pressure to ban Huawei products. The European Union is conducting a wider security review due by the end of December that will include steps to safeguard 5G networks.
The EU's top security official Julian King told reporters that the decision not to name problematic suppliers was not "ducking the issue." Instead, he said the report would empower EU countries to make informed choices.
Huawei is the world's largest supplier of telecoms equipment, and its market share in Europe is estimated at between 35% and 40%.
"We are pleased to note that the EU delivered on its commitment to take an evidence-based approach, thoroughly analyzing risks rather than targeting specific countries or actors," said a spokesperson for Huawei.
5G isn't just about fast mobile internet. Other technologies will be made possible with its ability to handle much more bandwidth, allowing the data from sensors, thermostats, cars and robots to work together in real time.
The EU report says critical sectors of the economy including energy, transport, banking and health would all be exposed to new risks as a result of being connected.
"Ensuring the security and resilience of 5G networks is therefore essential," the report states.
Some mobile network operators are meanwhile taking steps to diversify their suppliers beyond Huawei, Ericsson ( and )Nokia (, which have a stranglehold on the industry. )
Vodafone (, the world's second largest mobile network provider, said Monday that it would test Open Radio Access Networks (OpenRAN) in Britain, part of an effort to increase the number of firms that sell telecom network equipment. )