BRUSSELS—The European Union on Thursday imposed anti-dumping tariffs on some Chinese and Russian steel imports for the next five years in a fresh effort to protect domestic manufacturers struggling with overcapacity.

The duties, which range from 19.7% to 22.1% for Chinese companies and from 18.7% to 36.1% for Russian producers, apply to so-called cold-rolled steel, a product used in the packaging, automotive, construction sectors.

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