Binance has temporarily paused bitcoin withdrawals in response to a "stuck transaction causing a backlog," CEO Changpeng Zhao tweeted Monday morning.
Binance is the world's largest crypto exchange by trading volume, and the pause comes during a rapid sell-off in crypto markets. Zhao initially said, around 8 a.m. EDT, that the issue would be fixed in less than 30 minutes, before clarifying it would likely take longer.
Funds, he added, are "SAFU," referring to the Secure Asset Fund for Users insurance fund Binance set up for users four years ago. The fund is composed of Binance coin, Binance USD and bitcoin, and was valued at $1 billion in January, though the crypto crash means it's worth substantially less today.
A blog post from the company published at 9:15 a.m. said the issue was "due to an earlier batch of transactions getting stuck from low transaction fees submitted and hence, resulting in a backlog of Bitcoin network withdrawals. The Binance team is working on a solution to resume Bitcoin network withdrawals soon."
Withdrawals of bitcoin on other networks remain open, Binance added.
The announcement came amid a steep sell-off in cryptocurrencies. Bitcoin is already down nearly 14% over the past 24 hours, according to CoinMarketCap. Ether's value has fallen more than 15% in the same period. Most cryptocurrencies beyond the big names like bitcoin and ether have also fallen on hard times recently. Terra notably cratered last month, a collapse that was dire enough to catch the attention of Treasury Secretary Janet Yellen.
Platforms have also had a rough go. Only hours before Binance paused bitcoin transactions, crypto lending company Celsius stopped all withdrawals, swaps and transfers between accounts, citing market conditions and the need for "stabilizing liquidity." Other trading platforms that allowed crypto trading, such as Robinhood and Coinbase, have also seen their value shrink as crypto crashes.