Binance is considering ending business relationships with banks and services firms amid heightened scrutiny.

Binance has pulled back on some potential investments in the United States, its CEO Changpeng Zhao said on Friday, following a Bloomberg News report that said the leading crypto exchange was considering ending relationships with US business partners.

“We pulled back on some potential investments, or bids on bankrupt companies in the U.S. for now. Seek permission first,” Zhao wrote in a tweet, without elaborating.

The Bloomberg report, which cited an unnamed person familiar with the matter, said Binance is considering ending business relationships with banks and services firms in the US, amid heightened regulatory scrutiny of the company.

Binance is also reassessing US venture capital investments and will consider delisting tokens from any US-based projects, including the major stablecoin USD Coin, the report said.

Word that Binance may drop its US partners comes a day after the Reuters news agency reported that the global Binance exchange, which is not licensed to operate in the US, had secretly moved more than $400m from accounts held by its purportedly independent US partner. That money, according to company messages, was shifted to a trading firm managed by Zhao.

“Like every other blockchain company, we are conducting a careful cost-benefit analysis and will pivot our business as necessary to protect our global user base,” a Binance spokesperson said. The company did not immediately respond to questions on which US investments Binance had pulled back from.

US regulators stepped up scrutiny of crypto companies this year. The regulatory action comes after multiple meltdowns in the crypto sector last year that saw a string of key industry players in the US and beyond collapse.

On Monday, New York’s top financial regulator ordered the company behind Binance’s stablecoin to stop issuing the token.

Earlier this month Binance said it had suspended all dollar bank transfers after a US banking partner, Signature Bank, dialled back exposure to crypto firms.