The move means Chinese PV manufacturers can no longer import polysilicon and escape Beijing’s previously-imposed anti-dumping tariffs as long as the solar products in question were destined for export markets.

Analysts said the closing of the loophole – know as the ‘Process in Trade’ rule – is primarily aimed at US polysilicon producers such as Hemlock and REC Silicon.

The US authorities in June closed their own tariff-busting loophole, which saw Chinese PV module-makers avoid American punitive duties by using Taiwanese cells.

Despite