Chinese bitcoin exchanges Huobi and OKCoin – two of the country's "Big Three" markets – have announced that they will halt yuan-denominated trading by the end of October.

The twin statements indicate that, at least for now, the exchanges will continue to offer cryptocurrency-to-cryptocurrency trading services. That said, both exchanges are halting yuan deposits starting today.

According to Huobi and OKCoin, definitive information about the trading suspension will be circulated to users before September 30. More significantly, the exchanges will undertake a "gradual" process of unwinding its yuan-denominated markets, with an eye to complete that process by October 31.

The news comes after fellow China-based exchanges BTCC, ViaBTC and Yunbi all announced that they would shut their doors, citing statements from domestic regulators earlier this month. In the wake of BTCC's closure yesterday, both Huobi and OKCoin said that they had not received any notices or instructions to close.

Yet this morning, leaked documents indicated that verbal directives had been given to some exchanges regarding their closure. Notably among those instructions was the stipulation that user data be preserved and provided to the government. Cryptocurrency prices, in turn, saw continued turmoil in the wake of those developments.

The move to halt yuan-to-crypto trading represents a new phase in the ongoing saga around cryptocurrency regulation in China.

Earlier this month, China put a freeze on its domestic initial coin offering (ICO) space, declaring it an illegal form of fundraising. Exchanges and other websites providing ICO-related services subsequently moved to accommodate the new rules amidst the fallout, with investors in previously held ICOs set to be refunded their money.

That move came months after regulators in China moved to impose new anti-money laundering restrictions on the country's exchanges. In early 2017, the People's Bank of China made waves when it was revealed that officials had met with the leaders of the country's major bitcoin exchanges, followed by meetings with other representatives of the ecosystem and a months-long withdrawal freeze amid the upgrades.

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