In a move that customers have labelled very fishy, the Chinese government has ruled that rainbow trout can now be labelled and sold as salmon.

The seemingly bizarre move comes after complaints earlier this year that rainbow trout was being mislabelled.

In May, media reported that much of what was sold as salmon in China was actually rainbow trout, to widespread consternation from fish-buyers.

But instead of banning vendors from deceiving their customers, the China Aquatic Products Processing and Marketing Alliance (CAPPMA), which falls under the Chinese ministry of agriculture, has ruled that all salmonidae fish can now be sold under the umbrella name of “salmon”, reports the Global Times.

Rainbow trout and salmon are both salmonidae fish and look quite similar when filleted. However, salmon live in salt water and rainbow trout live in fresh water.

The ruling has been met with anger on the social media platform Weibo, where #RainbowTroutBecomesSalmon has been trending, according to the BBC.

The Global Times reports that the sale of salmon has increased in recent years in China, but that customers had begun complaining that some of what was marketed as salmon was actually trout.

Customers also voiced fears that trout, when eaten raw, as is common in China, could pass on parasites to humans. The China Fisheries Association refuted this claim saying rainbow trout was quarantined carefully and fed hygienically.

“Whether salmon has parasites does not depend on whether it is bred in sea water or fresh water,” it said.