Binance and its chief executive, Changpeng Zhao, are being sued by the Commodity Futures Trading Commission, the US commodity markets regulator, ina complaint that alleges the defendants "deliberately evasive of US law".

The move is the most significant U.S. enforcement action to date against the world's largest cryptocurrency exchange.

The CFTC said it had filed a civil enforcement complaint in a federal court in Chicago accusing Zhao and the three entities that operate Binance platforms of multiple violations of the Commodity Exchange Act and CFTC regulations. The complaint also accuses Binance's former chief compliance officer, Samuel Lim, of helping Binance carry out these violations.

According to the complaint, Binance's U.S. business continued to grow despite its public intention to block U.S. customers from accessing the platform.

Moreover, even after announcing the US restrictions, Binance told its most valuable US customers how to circumvent its compliance controls.

"Defendants ignored applicable federal law while growing Binance's U.S. customer base because it was profitable for them to do so," the CFTC complaint said. The regulator said it is seeking penalties including fines and a permanent trading ban.

Gretchen Lowe, the CFTC's chief counsel, said Binance put profits ahead of compliance with the law. The complaint alleges that Binance has been offering commodity derivatives trades (effectively betting on the price of cryptocurrencies rather than buying them outright) to U.S. clients since July 2019, in violation of relevant legal provisions, and that it has not yet registered with the CFTC.

Howard Fischer, a partner at New York law firm Moses & Singer, said the CFTC's action shows that U.S. regulators are taking concerted action against cryptocurrency exchanges, Earlier, the U.S. financial watchdog, the Securities and Exchange Commission (SEC), said it was considering potential enforcement action against Coinbase.

In a statement, the CFTC said: "Zhao was allegedly responsible for all major strategic decisions for Binance, including masterminding a secret conspiracy, instructing VIP customers in the United States to circumvent Binance's compliance controls, and instructing Binance employees to ensure that all communications regarding its controlled subversion controls were conducted through applications that facilitated the self-destruction of evidence."

A spokesperson for Binance called the CFTC's action "unexpected and disappointing." The company has been working with the CFTC for more than two years and has "made significant investments over the past two years to ensure that no U.S. users are active on Binance."

"Nevertheless, we intend to continue to work with regulators in the United States and around the world," they said. "The best path forward is to protect our users and work with regulators to develop a clear and thoughtful regulatory regime."