The European Union told its members on Wednesday that they should limit so-called high-risk 5G vendors, a category that includes the Chinese tech giant Huawei, but stopped short of recommending a ban on the firm, despite a lengthy and aggressive campaign by the Trump administration.

The recommendations are as far as the European Union can go in dictating policy to its member nations, whose governments will have the final word on whether and how they want to let Huawei help build their next generation of wireless telecommunications networks.

The European Union guidance, referred to as the “5G toolbox,” is a key moment in the bloc’s intensive work to help its members decide how to navigate fraught political and technical considerations as they and their wireless carriers prepare to invest billions of dollars in telecommunications infrastructure.

“We can do great things with 5G,” said Margrethe Vestager, a top official of the European Commission, the European Union’s executive body. “But only if we can make our networks secure.”