The world’s largest cryptocurrency exchange, Binance, instituted a pause on withdrawals of bitcoin Monday morning, founder and CEO Changpeng Zao announced on Twitter.
The news comes amid a steep decline in cryptocurrency prices, with bitcoin BTCUSD, -14.74% down more than 14% on the day, while ether ETHUSD, -17.80% prices slumped more than 18%.
Read more: Bitcoin tumbles through $24,000 in crypto crash. This chart shows how much worse a selloff could get.
Binance elaborated on the problem later Monday morning, saying that “a batch of bitcoin transactions got stuck” due to low transaction fees, “resulting in a a backlog” of bitcoin network withdrawals, in a series of tweets from the companies Twitter account.
“Our team is working on a solution to resume withdrawals as soon as possible,” it added. “Stay tuned for further updates and timelines.”
The pause in withdrawals comes amid heightened regulatory scrutiny of cryptocurrency exchanges by U.S. authorities. The Securities and Exchange Commission is reportedly investigating Binance Holdings Ltd. for potentially violating securities laws when it issued its BNB token, which provides traders on the platform with lower fees.
SEC Chairman Gary Gensler has also said that he sees cryptocurrency exchanges as a critical point of focus for U.S. regulators who want to bring transparency and investor protection to crypto markets.
“90% to 95% of the activity in the lending and trading of crypto happens on a platform,” like Binance and other crypto exchanges, Gensler said in a Feburary interview with MarketWatch.
“That activity, centralized on those platforms, they need the investor protection, the market integrity and anti-manipulation” rules that govern markets for other financial assets, he added. “I think the problem is, right now, the public isn’t well protected and there’s a lot of folks who are going to get hurt.”
Congress may also step in to bring more clarity to crypto regulations, after two bipartisan proposals were floated by U.S. senators last week that would give the Commodity Futures Trading Commission primary oversight of crypto markets, including exchanges like Binance that facilitate the buying and selling of decentralized digital assets.