Zhongwang, which has its European office in Frankfurt, is the world's second-biggest manufacturer of aluminium extrusions widely used in the transport, construction and electronics industries.

"We do not know if we are closing in Frankfurt yet, but we are going through a restructuring with some people leaving," an unnamed source at the company told Reuters on Monday.

"We do not know how much business will be done from China."

The company, which in March unveiled plans to spin off its extrusions business via a listing in Shanghai, on Sunday told Reuters that its Europe office is still in operation but its business "has scaled down due to the pandemic".

Zhongwang will continue to review and adjust its business strategy depending on the pandemic and market situation, it added.

Cui Ming, who worked as a Zhongwang key account manager in Germany, wrote in a LinkedIn post that his engagement in Europe had ended. As well as the coronavirus, two EU anti-dumping investigations and EU restrictions on the activities of big Chinese companies were behind the decision, Cui said.

His mobile phone was unreachable at the time of publishing.

The European Commission in February opened an investigation into whether China is dumping aluminium extrusions in the EU and this month launched a second investigation into flat-rolled aluminium products from China.

Zhongwang's sales in Germany totalled 132 million yuan ($19.2 million) in the first six months of the year, it said in an Aug. 28 filing, down more than half from a year earlier and accounting for only 1.5% of its total sales over the period.

($1 = 6.8647 Chinese yuan renminbi)

By Tom Daly and Michael Hogan