AliExpress to appeal penalty after European Union (EU) regulators found shortcomings in efforts to curb illegal, unsafe and counterfeit goods.

The largest Chinese e-commerce platform in the EU, AliExpress, has been fined €550 million ($629 million) for failing to tackle sales of illegal, unsafe and counterfeit products.

"The spread of counterfeit clothing, unsafe toys, dangerous cosmetics and other illegal and harmful products is not an unavoidable cost of shopping online - it is a failure by AliExpress to comply with its obligations under the Digital Services Act," European Commission Vice President Henna Virkkunen said on Monday.

It is the largest fine ever imposed under the Digital Services Act (DSA), which sets out clear rules for online services in the EU, targeting especially very large online platforms.

AliExpress said it will appeal the "disproportionate" fine, saying it considers the penalty excessive.