A WTO panel handed a victory to the United States earlier this month, rejecting all four of China's claims and saying the US measures did not breach global trade rules.

China said last week it would appeal the decision.

At the private meeting, China's delegate expressed "deep concern with the systematically harmful findings made by the panel report," according to a statement sent by the Chinese delegation.

"The erroneous and dangerous signal sent by this panel report to WTO members will lead to the abuse of safeguard measures and thus seriously undermine the rules-based multilateral trading system," it added, saying the ruling could encourage protectionism.

The United States imposed a system of tariffs and a quota in 2018 after US producers complained that imports of certain crystalline silicon photovoltaic cells had increased to such an extent that US domestic industry risked serious harm.

The "safeguard" measures are due to be in place for four years, with annual reductions in the duty rates from an initial 30 per cent.

The duties have applied to solar modules and, beyond a set quota, to solar cells.

China's appeal will have no immediate effect since the top WTO dispute settlement body does not have enough judges to function.

That is because the administration of former US president Donald Trump blocked judge appointments to the body and paralysed its functions.

"The United States is disappointed that China has now decided to press onward by appealing the Panel report in spite of overwhelming evidence of the damaging effects of China's non-market practises...," the US delegate said at the same meeting on Monday.

Australian Associated Press