The United Kingdom’s financial markets regulator, The Financial Conduct Authority (FCA), had a busy Sunday on Oct. 8, adding several crypto exchanges to its warning list of non-authorized firms that customers “should avoid.”

143 new entities were added to the warning list, including major exchanges such as Huobi/HTX and KuCoin, founded in China and Singapore respectively. The warning list doesn’t tell much apart from the “You should avoid dealing with this firm” imperative.

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However, in the U.K., firms permitted to “carry out crypto asset activities” must either be registered with the FCA or have been granted temporary status to operate. In July, Jayson Probin, crypto financial promotions lead at the FCA, suggested that failure to comply could result in criminal charges:

“We will take robust action against persons illegally promoting to U.K. consumers. This may include, but it is not limited to, placing firms on our warning list requesting take downs of websites, social media accounts, apps and all other promotions that are in breach, and enforcement action.”

In August, the FCA revealed that since 2020, it has received 291 applications for registration and approved only 38 of them, which is roughly 13%. At the time of publication, the FCA’s list of registered crypto asset providers includes 42 entities, such as Bitstamp, Revolut and Gemini. 

PayPal has recently halted crypto transactions for its U.K. customers until it figures out how to comply with all the FCA’s requirements. Dubai-headquartered cryptocurrency exchange Bybit suspended all its services in the United Kingdom in late September due to “regulatory changes.”