Gary Gensler, chairman of the Securities and Exchange Commission (SEC), wants Senator Elizabeth Warren to help clean up cryptocurrency exchanges.

In the four months since taking office, Gensler has repeatedly raised concerns about the risks of cryptocurrency trading platforms. He wrote to Warren on Aug. 5 that regulators needed more resources to protect investors. He also said lawmakers should give regulators a clear mandate to formulate regulations for such exchanges, including the decentralization of financial trading venues.

"We need additional authority to prevent regulatory oversight in transactions, products and platforms," he said in writing in response to a question raised by Mr Warren about how he plans to manage the industry.

Gensler, who previously taught digital assets at the Massachusetts Institute of Technology, said supporters of cryptocurrency were disappointed by his desire to bring the asset class into government regulation. He told Warren that he was particularly concerned about the so-called "stablecoin", which plays an indispensable role in transactions.

For her part, Warren hinted that she was willing to support more controls on digital assets.

"cryptocurrencies are the wilderness of our financial system and there is an urgent need for rules," Mr Warren said in a statement. "I will continue to engage with the Securities and Exchange Commission and other federal regulators to fill regulatory gaps through legislation."