The case comes as the 27-member European Union wants the digital economy to be a key part of its economic recovery and demands a greater opening of Chinese markets.

Europacable, which brought the complaint on behalf of the EU producers, said some 1.2 million kilometres (745,000 miles) were sold in Europe last year, with 15-20% coming from China, in a total EU market worth about 1 billion euros ($1.16 billion).

Chinese imports rose by 150% from 2016 to 2019, the industry group said.

EU anti-dumping investigations take up to 15 months, but provisional duties can be put in place within eight. Final tariffs, if imposed, would normally apply for five years.

The largest producers in the EU are Italy's Prysmian Group, U.S. company Corning and France-based Nexans and Acome.

Major Chinese optical fibre cable makers include Yangtze Optical FC, Hengtong Group, Fiberhome and Futong.

The Commission has already carried out a series of investigations into glass fibre products from China and imposed tariffs. It also has 29 ongoing trade defence investigations, 18 of them including products from China.

(Reporting by Philip Blenkinsop; Editing by Mark Potter and David Evans)